Make the spicy peanut sauce: whisk all sauce ingredients together until smooth & creamy, set aside
Make noodle filling: break noodles into small bits, cook according to package directions, when noodles are cooked, drain and toss in a bowl with sesame oil and red pepper flakes
Make vegetable filling: use a box grater or mandolin, slice cucumber, carrot and bell pepper into thin slices. Whisk together rice vinegar, sugar, fish sauce and lime juice in a large bowl. Add vegetables and scallions, toss to coat.
Soften rice paper wrappers with warm water. Follow directions on the package. Working on one at a time, soften rice paper wrapper, slowly remove it from the water and place it on a plate.
Fill the center of the softened wrapper with 1-2 tbsp. cooked noodles and top with sliced vegetables, top with cilantro and mint leaves.
Roll up wrapper, fold sides in first like a burrito, then roll the long way until it is rolled all the way up, tight and snug
Continue until all wrappers are filled, place each one on a cookie sheet and cover with a damp paper towel until they are all finished
When ready to serve, slice each roll in half and serve with peanut dipping sauce