Position two racks in lower and upper levels of oven. Preheat oven to 250°F/121°C. Coat two rimmed half-sheet pans with nonstick spray and set aside.

Coat the inside of a very large mixing bowl with nonstick spray and also coat a large silicone spatula. Pour popped corn into the bowl.

Place butter, brown sugar, corn syrup, rice malt syrup (is using), molasses, ginger, cinnamon, cloves and salt in a saucepan and stir to combine. Bring to a light boil over medium heat, swirling pan once or twice (but do not stir). Boil for 4 minutes; the mixture should darken and thicken (the bubbles will open more slowly). Remove from heat, add baking soda and vanilla and swirl pan quickly (watch for it bubbling up) to combine then slowly pour over the popped corn, folding as you go with the nonstick spray coated spatula. Keep folding to evenly coat the popped corn. Be patient! It will work.

Scrape onto the two pans, dividing evenly, and tamp down into an even layer. Bake for 1 hour, turning the popped corn over with a broad metal spatula about every 15 minutes. This will help the popped corn stay evenly coated with gingerbread caramel. Cool on racks completely then get into airtight bags or containers quickly - to preserve it best but also to keep yourself from eating it all! Just TRY not to eat this stuff; you have been warned.