Our Low FODMAP “Key Lime” Cupcakes showcase the flavor of that beloved dessert, key lime pie. And, to make things easier than ever, we are starting with Rachel Pauls Vanilla Cake Low-FODMAP Baking Mix – a boxed mix that is certified low FODMAP. Vanilla cake on top of a layer of low FODMAP, gluten-free graham cracker crust, lime curd filling and a zesty lime cream cheese frosting complete the recipe, which is party-worthy.
Key Limes vs. Persian Limes
Key limes (Citrus × aurantiifolia) and standard supermarket limes – which are Persian limes (Citrus × aurantiifolia) – are not the same fruit. There is much more info below in the FAQ section. The reason why we are discussing them right here up front is because key lime pie uses key limes, and we are paying homage, but key limes have not been lab tested for FODMAPs.
We suggest using conventional Persian lime juice for this recipe – not only because we think it makes a wonderful cupcake, but also because it has been lab tested. Read more below.
Desserts With Components
Some desserts are comprised of components, such as these Low FODMAP “Key Lime” Cupcakes. There is the cake portion, created with Rachel Pauls Vanilla Cake Low FODMAP Baking Mix, the graham cracker crust (just like key lime pie), lime curd for the filling and a tangy zesty cream cheese frosting.
The lime curd can be made several days ahead, if you like, to streamline the process. You could even make the graham cracker crust and press it into the cupcake tins the day before you’re going to bake. You could bake the crust and cupcake part the day before serving, too, but I think they are best if you bake the crust and cupcakes, fill the cupcakes and frost the cupcakes the day you were going to serve them.
Rachel Pauls Baking Mixes & Low FODMAP Products
By the way, Rachel Pauls has a few baking mixes. Try the Chocolate Cake mix and Fudgy Brownie mix, too.
Rachel Pauls also makes a variety of Happy Bars snack bars (6 flavors – read about them in our Energy Bar article), an array of low FODMAP jerky (Original, Tangy, and Hot) and also convenient spice blends (Taco, Steak and Italian) and soup bases (Beef, Vegetable and Chicken)!
Did you know that every Rachel Pauls product is lab tested and certified low FODMAP? Yes! Read more in our in-depth article with Rachel Pauls herself.
Check out Rachel Pauls cookbook as well.
Frequently Asked Questions
In the U.S. the standard supermarket lime is the Persian lime. They have a dark green skin and tart flavor. Key limes (Citrus × aurantiifolia) are smaller, lighter and yellower in color and contain more seeds and are not as easy to find. They are often described as having a stronger lime flavor and being more aromatic. I agree with the aromatic part, and would even say that they can be more nuanced and complex, but I actually find them less sharp than Persian limes and have a flavor all their own.
While the traditional key lime pie uses key limes, they have not been lab tested for FODMAPs, which is why we call this cupcake “key lime” using quotes. We are paying tribute to key lime pie, but to be sure to be low FODMAP compliant, please use fresh lime juice made from Persian limes.
Well, you could, in the sense that the recipe will work, but the flavor will not be the same as if you use fresh juice, and, as stated above, key limes have not been lab tested for FODMAPs. We suggest not using any kind of bottled lime juice. Fresh lime juice makes all the difference with this recipe.
The low FODMAP diet is not a dairy-free diet; it is, however, lower in lactose. Some dairy products, such as hard cheeses (think cheddar, Swiss, parmesan etc.) are naturally low enough in lactose to be low FODMAP. Softer cheeses and dairy products like sour cream, cottage cheese and cream cheese do have low FODMAP serving sizes, but they are small-ish – 2 Australian tablespoons.
We have a Lactose-Free Cream Cheese Frosting recipe for you elsewhere on the site, which takes advantage of Green Valley Creamery lactose-free cream cheese. It is a fantastic product, but not everyone has access to it. To make this recipe more user-friendly I have used conventional cream cheese. If you stick to the recommended serving size of 1 cupcake, your serving size will remain low FODMAP.
This frosting recipe will not work as written with the lactose-free cream cheeses we have worked with in the Test Kitchen.
And, also by the way, we love Philadelphia cream cheese and there have been times that we have used supermarekt brands and not gotten the same results in our recipes. The texture of the frosting has ended up too loose when other brands have been used. Alwways use the ingredients recommended for best results.
Note that this recipe is not dairy-free. There is also butter in the crust, and milk in the cake component.
These cupcakes are fancy! The vanilla cake batter is baked right on top of a layer of graham cracker crust (to make them more key lime pie-like, along with the lime filling). I like to use Nairn’s Gluten Free Original Oat Grahams, but we never have them in our markets, so I always have to pre-order them. They are easy enough to find online, but I admit that is not convenient.
They do contain golden syrup, which has been lab tested for FODMAPs and has a small low FODMAP serving size. If you stick with the suggested serving size you will be Elimination Phase compliant.
The low FODMAP diet is actually neither gluten-free nor wheat-free, and if you do not need to be gluten-free and you know your tolerance to the fructans in wheat, you could use conventional graham crackers instead. The amount of butter needed for the crust to be the right consistency might vary.
Making “Key Lime” Cupcakes
For the Lime Curd: Use a Microplane zester to remove zest from the limes. It will be light and fluffy.
Whisk the sugar, lime juice and eggs together in a non-reactive saucepan.
Whisk in small chunks of butter.
Cook over medium-low heat, whisking frequently. When the mixture begins to bubble around the edges, lower the heat and whisk constantly until the mixture thickens and reaches 180°F (82°C). (The temperature is more important than the time it takes, and the curd should not boil vigorously.) The curd will thicken and form a soft shape when dropped from a spoon. It will also begin to look a bit translucent. If desired, stir in the zest after removing from the heat. The curd is great tasting, and smoother, without the zest. Add if you want an extra lime boost.
Let curd cool to room temperature, stirring occasionally to release the heat. Refrigerate for at least 6 hours before using, or up to 1 week in an airtight container.
For the Crust: Position racks in upper and lower third of oven. Line 30 cupcake wells with fluted-paper liners.
Using a food processor fitted with a metal blade, pulse the graham crackers into very fine, evenly ground crumbs. Pulse in the sugar and enough melted butter until the crumbs are evenly moistened.
Scoop about a tablespoon of the crumb mixture into each cupcake liner and pat down firmly to create an even layer of graham cracker crust. No need to pre-bake.
For the Cupcakes: Prepare the batter as directed on the box using the eggs, oil and milk.
The batter comes together in a flash! You can even do it by hand with a bowl and whisk.
Divide batter equally over crusts.
Bake for about 20 minutes or until a toothpick inserted in the center tests clean.
Cool completely on rack. You can make the cupcakes the day before serving. Store in airtight container at room temperature.
For The Cream Cheese Frosting: In a large bowl with an electric mixer on medium-high speed, beat cream cheese until smooth, about 2 minutes; you want to eliminate any lumps at this stage. Add butter and beat on medium-high speed until very smooth, scraping down the sides of the bowl once or twice. Add half the sugar, beating on low speed until absorbed, then beat in remaining sugar until smooth and creamy. Beat in lime juice, and zest, if using. Frosting is now ready to use and is best if used immediately. It may be refrigerated in an airtight container for 4 days. Bring to room temperature and re-beat after storing.
For Assembly: The day of serving, place chilled lime curd in plastic pastry bag fitted with a round tip, such as a Wilton #1A or #230.
Insert tip into the center of each cupcake and fill with about a tablespoon of lime curd. You will not be able to see it; just fill until you see the top of the cupcake expand a bit. If a dollop of curd rests on top of the cupcake, that’s okay.
Top each cupcake with frosting, either using a small offset spatula, or we used a Wilton 1M star tip to make swirls.
The cupcakes can be served as is, or add a pinch of graham cracker and a key lime slice to each cupcake – which are optional.
FODMAP Information
Our recipes are based on Monash University and FODMAP Friendly science.
- Butter: Both Monash University and FODMAP Friendly have lab tested butter. Monash states that a low FODMAP Green Light portion is 1 tablespoon or 19 g and also states that “butter is high in fat and does not contain carbohydrates (FODMAPs)”. FODMAP Friendly gives it a “Pass” at 1 tablespoon or 19 g. Both recommended serving sizes are presented as part of healthy eating guidelines, not as maximum FODMAP serving size. Fat can affect guy motility and trigger IBS symptoms in some people. Eat to your tolerance.
- Dairy: The low FODMAP diet is not a dairy-free diet. It is however, low in lactose. Many dairy ingredients are low in lactose, such as heavy cream and many cheeses.
- Eggs: Eggs are high in protein and do not contain carbohydrates, according to Monash University.
- Lime Juice: Monash University has lab tested lime juice and it is low FODMAP in 1 cup (250 g) amounts (double that of lemon juice, as an interesting fact).
- Oil: All pure oils are fats and contain no carbohydrates, therefore they contain no FODMAPs.
- Sugar: Monash University and FODMAP Friendly have both lab tested white, granulated sugar. Monash states that a Green Light low FODMAP serving size of white sugar is ¼ cup (50 g). FODMAP Friendly simply states that they have tested 1 tablespoon and that it is low FODMAP. Regular granulated white sugar is sucrose, which is a disaccharide made up of equal parts glucose and fructose. Sucrose is broken down and absorbed efficiently in the small intestine.
Please always refer to the Monash University & FODMAP Friendly smartphone apps for the most up-to-date lab tested information. As always, your tolerance is what counts; please eat accordingly. The ultimate goal of the low FODMAP diet is to eat as broadly as possible, without triggering symptoms, for the healthiest microbiome.
This Recipe Was Generously Sponsored by Rachel Pauls Foods
Low FODMAP “Key Lime” Cupcakes
Our Low FODMAP "Key Lime" Cupcakes showcase the flavor of that beloved dessert, key lime pie. And, to make things easier than ever, we are starting with Rachel Pauls Vanilla Cake Low-FODMAP Baking Mix – a boxed mix that is certified low FODMAP. Vanilla cake on top of a layer of low FODMAP, gluten-free graham cracker crust, lime curd filling and a zesty lime cream cheese frosting complete the recipe, which is party-worthy.
Low FODMAP Serving Size Info: Makes 30 cupcakes; 30 servings; 1 cupcake pr serving
Ingredients:
Key Lime Curd:
- 1 cup (198 g) sugar
- ¾ cup (180 ml) fresh squeezed lime juice
- 2 large eggs, at room temperature
- 4 tablespoons (57 g; ½ stick) unsalted butter, at room temperature, cut into pieces
- 1 tablespoon lime zest
Graham Cracker Crust & Cupcakes:
- 4- ounces (115 g) Nairn’s Gluten Free Oat Grahams
- 3 tablespoons sugar
- 2 to 3 tablespoons melted unsalted butter
- 1 box (26-ounces/737 g) Rachel Pauls Vanilla Cake Low FODMAP Baking Mix
- 4 large eggs, at room temperature
- 1 cup (240 ml) canola oil or other neutral flavored oil
- 1 cup (240 ml) 2% lactose-free milk, at room temperature
Cream Cheese Frosting & Decoration:
- 1- pound (455 g) full-fat block cream cheese, such as Philadelphia brand, cut into pieces, at room temperature
- ½ cup (113 g; 1 stick) unsalted butter, at room temperature, cut into pieces
- 3 cups (270 g) sifted confectioners’ sugar
- 1 tablespoon key juice
- Key lime zest; optional
- Low FODMAP graham cracker crumbs
- Key lime slices; optional
Preparation:
-
For the Lime Curd: Whisk the sugar, lime juice and eggs together in a non-reactive saucepan. Whisk in small chunks of butter. Cook over medium-low heat, whisking frequently. When the mixture begins to bubble around the edges, lower the heat and whisk constantly until the mixture thickens and reaches 180°F (82°C). (The temperature is more important than the time it takes, and the curd should not boil vigorously.) The curd will thicken and form a soft shape when dropped from a spoon. It will also begin to look a bit translucent. If desired, stir in the zest after removing from the heat. The curd is great tasting, and smoother, without the zest. Add if you want an extra lime boost.
-
Let curd cool to room temperature, stirring occasionally to release the heat. Refrigerate for at least 6 hours before using, or up to 1 week in an airtight container.
-
For the Crust: Position racks in upper and lower third of oven. Line 30 cupcake wells with fluted-paper liners.
-
Using a food processor fitted with a metal blade, pulse the graham crackers into very fine, evenly ground crumbs. Pulse in the sugar and enough melted butter until the crumbs are evenly moistened. Scoop about a tablespoon of the crumb mixture into each cupcake liner and pat down firmly to create an even layer of graham cracker crust. No need to pre-bake.
-
For the Cupcakes: Prepare the batter as directed on the box using the eggs, oil and milk. Divide batter equally over crusts. Bake for about 20 minutes or until a toothpick inserted in the center tests clean. Cool completely on rack. You can make the cupcakes the day before serving. Store in airtight container at room temperature.
-
For The Cream Cheese Frosting: In a large bowl with an electric mixer on medium-high speed, beat cream cheese until smooth, about 2 minutes; you want to eliminate any lumps at this stage. Add butter and beat on medium-high speed until very smooth, scraping down the sides of the bowl once or twice. Add half the sugar, beating on low speed until absorbed, then beat in remaining sugar until smooth and creamy. Beat in lime juice, and zest, if using. Frosting is now ready to use and is best if used immediately. It may be refrigerated in an airtight container for 4 days. Bring to room temperature and re-beat after storing.
-
For Assembly: The day of serving, place chilled lime curd in plastic pastry bag fitted with a round tip, such as a Wilton #1A or #230. Insert tip into the center of each cupcake and fill with about a tablespoon of lime curd. You will not be able to see it; just fill until you see the top of the cupcake expand a bit. If a dollop of curd rests on top of the cupcake, that’s okay. Top each cupcake with frosting, either using a small offset spatula, or we used a Wilton 1M star tip to make swirls. The cupcakes can be served as is, or add a pinch of graham cracker and a key lime slice to each cupcake.
Notes:
FODMAP Information
Our recipes are based on Monash University and FODMAP Friendly science.
• Butter: Both Monash University and FODMAP Friendly have lab tested butter. Monash states that a low FODMAP Green Light portion is 1 tablespoon or 19 g and also states that “butter is high in fat and does not contain carbohydrates (FODMAPs)”. FODMAP Friendly gives it a “Pass” at 1 tablespoon or 19 g. Both recommended serving sizes are presented as part of healthy eating guidelines, not as maximum FODMAP serving size. Fat can affect guy motility and trigger IBS symptoms in some people. Eat to your tolerance.
• Dairy: The low FODMAP diet is not a dairy-free diet. It is however, low in lactose. Many dairy ingredients are low in lactose, such as heavy cream and many cheeses.
• Eggs: Eggs are high in protein and do not contain carbohydrates, according to Monash University.
• Lime Juice: Monash University has lab tested lime juice and it is low FODMAP in 1 cup (250 g) amounts (double that of lemon juice, as an interesting fact).
• Oil: All pure oils are fats and contain no carbohydrates, therefore they contain no FODMAPs.
• Sugar: Monash University and FODMAP Friendly have both lab tested white, granulated sugar. Monash states that a Green Light low FODMAP serving size of white sugar is ¼ cup (50 g). FODMAP Friendly simply states that they have tested 1 tablespoon and that it is low FODMAP. Regular granulated white sugar is sucrose, which is a disaccharide made up of equal parts glucose and fructose. Sucrose is broken down and absorbed efficiently in the small intestine.
Please always refer to the Monash University & FODMAP Friendly smartphone apps for the most up-to-date lab tested information. As always, your tolerance is what counts; please eat accordingly. The ultimate goal of the low FODMAP diet is to eat as broadly as possible, without triggering symptoms, for the healthiest microbiome.
Nutrition
All nutritional information is based on third-party calculations and should be considered estimates. Actual nutritional content will vary with brands used, measuring methods, portion sizes and more. For a more detailed explanation, please read our article Understanding The Nutrition Panel Within Our Recipes.
No stars (yet) only because I have yet to attempt this recipe… But, man, you are speaking my language here! I adore Key Lime Pie. Many years ago a worked at a restaurant where the owner’s wife would make a Key Lime pie on a shortbread crust and it was divine. Last summer I made paleo “Key Lime” Pie Bites for my father’s birthday. They were tiny and delicious but even just two “bites” didn’t do my tummy any favors. I’ve been eyeing your Key Lime Pie recipe but hesitate because (1) it’s just me at home and I will probably eat the whole thing in one weekend and (2) it seems like a lot of work just for me. These cupcakes, however, are less fussy and have more built-in portion control. Keep a few for me and bring the rest in for my coworkers. Okay so, please post something about your results with this recipe for me, my fellow Low-FODMAPers. I want to know how these cupcakes turned out for you!
We hope to hear from folks, too! I could eat this curd by the spoonful!
I noticed that Rachel’s vanilla cake mix has xathan gum in it. Since this can be problematic for those of us with IBS, can it be considered low FODMAP?
Xanthan gum, as well as guar gum and many other gums, are low FODMAP. If you have a sensitivity to gums, as many do, then this would not be a great product for you – but it is low FODMAP. Here is some more info on Xanthan.