Follow noodle package directions for rinsing or cooking noordles. Drain and rinse under cold running water. Drain again. Place shrimp in a seive. Rinse under cold running water and drain. Horizontally slice shrimp in hald, keeping the half-circle shape. Trim any fat from chicken and pork. Using a very sharp knife, slice chicken and pork into thin bite-size strips. If very moist, pt dry with paper towel.
Cut bok choi across leaves into 1/2 inch strips. Cut broccoli into bite-size peices. Then drain baby corn, bamboo shoots and water chestnuts and discard their liquids.
Stir can of broth with oyster sauce, soy sauce and sugar. Measure out cold water and cornstarch, but do not mix. Cornstarch may clump if left standing. Before beginning to cook, be sure to have all the ingredients prepared and placed close to the stove.
Heat 1 Tbsp of vegetable oil in a wok or shall wide-bottomed saucepan or deep wide frying pan over medium-high heat. Whn hot, add chicken strips, stirring rapidly with a metal spatula or wooden spoon to keep strips separate and evenly coated with oil. Cook, stirring occasionally, until chicken loses its pink colour and has lightly browned, from 5-6 minutes. Then add garlic and stir until softened, about 2 minutes.
Pour in broth mixture. Stir occasionally to bring up browned bits while bringing to a low boil. Then stir in shrimp and broccoli and place bok choi over top. Cover and steam until vegetables are bright green and juat beginning to wilt, no more than 3 minutes.
Meanwhile, stir cornstarch with water until dissolved. Pour over stir-fry, until sauce is clear and thickened, about 2 more minutes. Stir in barbecued pork, baby corn, water chestnuts, bamboo shoots and sesame oil. Cover and heat 1 minute. Then remove pan from heat and cover.
Heat remaining 1 Tbsp vegetable oil in a large nonstick frying pan over medium to medium-high heat. When hot, add drained noodles. Spread evenly in pan. Saute, without stirring, until noodles turn golden, from 2 to 3 minutes per side. The should be crispy, as with hash browns. Resist the impulse to stir, or will not get crisp as they should be. Invert onto a large heated platteror serving bowl. Top with stir-fried vegetables and meat. Serve immediately with a shaker of hot pepper flakes and extra soy for those who want to spice it up a bit.
Make-ahead - Slice and prepare all ingredients. Place in individual containers or bowls, tightly cover and refrigerate for up to half a day. Starting to cook with chilled ingredients will require slightly longer stir-frying time.