Create a simple syrup in a large pot by whisking the sugar, vinegar, pineapple juice and lemon juice over medium high heat until the sugar dissolves. Turn up the heat and bring to a boil for 2 minutes. Turn off the heat and let sit while you prep the remaining ingredients.
Slice the pineapple in rings and grill them until the sugars begin to caramelize and creates grill marks on both sides.
Lightly char the skins of the Naga Vipers (or any hot peppers you choose) over an open flame or on a searing hot grill pan. Do not grill your red and yellow bell peppers in order to maintain some crunch and texture in the sauce. (roasting the pineapple and hot peppers will bring out their inherent sweetness and richness.
Make sure the Vipers are super finely chopped. If you want to tone down the heat slightly carefully remove the seeds. (I used my chopper to make sure the peppers were in super tiny pieces so no one bites into a large piece of super hot pepper.)
Next, finely chop all fruit, peppers and onion into 1/4" pieces (or smaller).
Stir the remaining ingredients into the simple syrup you prepared earlier. Stir in the cornstarch (mixing with a few tablespoons of water first to create a slurry). Bring the mixture to a boil and the turn down the heat to simmer for 5-10 minutes. The consistency should be syrupy and chunky.
