These crispy rolls are made with Vietnamese rice paper huge, round, translucent and very brittle. If you cannot find these exotic rice paper sheets, you can use filo dough instead (See Cook's Note). I must say, the first time I used these rice papers I almost gave up after only three minutes. Be patient and practice a bit. Once you get the hang of it, the rest will go smoothly. Be sure to use plenty of water when spraying the sheets, roll as quickly as possible and keep the sheets covered as you work. A challenge indeed, but well worth the effort. Rice papers as well as cellophane noodles can be found in any Asian supermarket.
Soak the cellophane noodles in warm water for 2 or 3 minutes. Cut into 4" lengths and drain. Cook in boiling water until done, about 4 or 5 minutes. Drain and set aside.
Cook onions, green peppers, garlic and jalapeno peppers in the sesame oil over high heat until wilted. Stir frequently to prevent burning. When the vegetables are wilted, add the shiitake mushrooms and cook over low heat until they are soft but not mushy. Place in a large bowl and cool. When the mixture is cool, add all the remaining ingredients except the rice paper and vegetable oil. Taste and adjust seasonings.
To assemble: Take one sheet of rice paper out of the package, dip in a large bowl of water, or spray using a plastic spray bottle, and lay out on a flat surface. Quickly place about 3 Tbs of the filling on the bottom of the round and roll up, tucking the ends in as you go. Seal with more water and set aside, seam side down. Make all rolls in this fashion. Heat about 2" of vegetable in a large skillet. When the oil it hot, but not smoking, add the rolls in batches and cook until golden brown on all sides. Remove from pan and drain on lint-free towels; do not use paper towels as the wrappers will stick to the paper. Serve immediately.
If using filo dough, cut sheets into long rectangles, approx. 6x8" long. Place some filling at the bottom of each piece of filo dough and roll up, tucking in the ends as you go. Brush with melted unsalted butter to seal. Cook in vegetable oil until golden brown. Be sure to cover the stack of filo dough at all times with a damp cloth to prevent it from drying out.