Recipes | Dinner

Sesame Crusted Ahi Tuna with Pickled Cucumbers Certified Low FODMAP by Monash University


Tuna: Beyond Sushi

Seared tuna steaks are very easy to make at home as long as you can find very fresh fish. Shop in a dedicated fish store if possible or buy from a supermarket where you can chat with the counter person. Signs might say “sushi grade”; “ahi” and often bluefin, yellowfin and big eye tuna are prime candidates for serving fairly raw with just a sear on the outside.

Monash University Certified Low FODMAP Sesame Crusted Tuna & pickled cucumbers sliced and laid out on a white square plate with dipping sauce.
What’s Black & White and Red Inside?

Here, for our Sesame Crusted Ahi Tuna Steaks with Pickled Cucumbers, we coat the fish with black and white sesame seeds for a delectable crunchy crust that contrasts beautifully with the silken, rare fish with its gorgeous deep pink/red color.

Monash University Certified Low FODMAP Sesame Crusted Tuna sliced on a plate.

The salty soy dipping sauce and the cool, sweet and hot, tangy cucumbers make this dish restaurant worthy. It’s fancy enough for guests, or halve the recipe and serve as a romantic dinner for two. (Make the whole batch of pickled cucumbers, as they are great to snack on anytime).

Monash University Certified Low FODMAP Sesame Crusted Tuna & pickled cucumbers sliced and laid out on a white square plate with dipping sauce.

Sesame crusted tuna & Pickled cucumbers no scallions

Sesame Crusted Ahi Tuna Steaks with Pickled Cucumbers

“One serve of a meal made in accordance with this recipe is low in FODMAPs and can assist with following the Monash University Low FODMAP diet™."

This dish features sushi grade ahi tuna that is seared lightly after being coated with two colors of sesame seeds. The pickled cucumbers on the side are more than a fresh, crunchy condiment - they are a mini salad that cuts through the richness of the tuna.

Makes 4 servings


Pickled Cucumbers:

  • 3 tablespoons rice wine vinegar
  • 3 tablespoons sugar
  • 11/2 tablespoons water
  • Heaping 1/2 teaspoon kosher salt
  • Scant 1/2 teaspoon chilli powder (ground red serrano chile)
  • 2 medium sized Persian cucumbers or 1 English hothouse cucumber

Dipping Sauce:

  • 1/4 cup (60 ml) low sodium soy sauce (use gluten-free if following a gluten-free diet)
  • 2 tablespoons freshly squeezed lime juice
  • 1 tablespoon plus 1 teaspoon sugar
  • 2 teaspoons finely chopped fresh ginger root
  • 2 tablespoons finely sliced scallions, green parts only

Ahi Tuna:

  • 4, 4 ounce (115 g) fresh ahi tuna steaks, about 1 inch (2.5 cm) thick, skin removed
  • 3 tablespoons black sesame seeds
  • 3 tablespoons hulled sesame seeds
  • Kosher salt
  • Freshly ground black pepper
  • 1 tablespoon plus 1 teaspoon Low FODMAP Garlic-Infused Oil, made with vegetable oil or purchased equivalent


  1. For the Cucumbers: Whisk together the vinegar, sugar, water, chilli and salt in a small saucepan. Bring to a boil over medium-high heat and stir until sugar dissolves, just a minute or two. Remove from heat and pour into a non-reactive airtight storage container. Wash and dry cucumbers then slice very thinly crosswise. If using the long English cucumber, you will need about 9 inches (23 cm) of it. (Save the rest for salad or snacking). Add cucumbers to the warm pickling mixture. Allow to cool, then cover and refrigerate at least 1 hour or up to overnight.
  2. For the Sauce: Whisk together the soy sauce, lime juice, sugar and ginger in a small bowl. Sprinkle scallions on top and let sit while you prep and cook the tuna.
  3. For the Tuna: Remove fish from refrigerator and set aside. Place both kinds of sesame seeds in a wide bowl and season with salt and pepper, tossing all ingredients together. Place the tuna steaks, once at a time, in the bowl and use fingers to press sesame mixture onto both broad sides of the fish filets.
  4. Heat oil in a large nonstick saucepan over medium-high heat until shimmering. Add tuna steaks and sear for a minute or two or just until the sesame seeds begin to smell fragrant and take on a bit of color. Flip filets over and cook second side as for the first. You can use tongs to help sear the tuna steak’s sides, if you like. The fish will remain rare and pink in the center. Remove to a cutting board and allow to sit for a minute. Slice tuna against the grain about 1/4 inch (6 mm) thick into slabs. Fan slabs of fish out on plates, arrange a mound of pickled cucumbers alongside and drizzle with sauce. Offer extra dipping sauce in small bowls. Serve immediately.