For the Chili Mayonnaise: In a small bowl, mix together the mayonnaise, chili sauce, lemon juice, fish sauce, garlic, and brown sugar.
For the Vegetable Rolls: In a medium mixing bowl, mix together the red bell pepper, yellow bell pepper, carrot, mint, and basil. Add the Chili Mayonnaise and toss well.
Lay a damp kitchen or paper towel on a work surface. Soak a rice paper round in warm water for 20 to 30 seconds until softened. Place the rice paper on the damp towel. Lay a lettuce leaf in the middle of the rice paper and spoon some of the vegetable mixture on top. Place 1/4 cup of the cellophane noodles on top of the vegetable mixture. Roll the rice paper around the filling and seal the ends with a little water. Repeat with the remaining ingredients.
Store the finished vegetable rolls in the refrigerator for up to 6 hours wrapped in damp paper towels.