Step 1

Place sliced chilies in small bowl. Pour boiling water over to cover. Let sit 10 minutes, then drain. Add vinegar, 1 teaspoon soy sauce, sugar, and 1/2 teaspoon salt and stir to combine. Allow to cool. For best results, refrigerate at least overnight. Chilies can be stored in an airtight container in the refrigerator for up to 1 month.

Step 2

For the stir-fry: Heat 3 tablespoons oil in wok over medium heat until shimmering. Add shallots, garlic, and mushrooms. Cook until mushrooms have softened and are beginning to brown, about 8 minutes.

Step 3

Increase heat to medium high and stir in bok choy. Cook until beginning to wilt, about 1 minute. Add remaining 3 tablespoons oil. Add shrimp, softened vermicelli, 2 tablespoons soy sauce, white pepper, and sprouts.

Step 4

Cook, stirring, until seasonings are combined with noodles, shrimp are cooked through, and noodles are beginning to brown on bottom of pan (add extra oil if beginning to stick), about 2 minutes. Season to taste with salt and/or soy sauce. Serve immediately with pickled chilies on the side.