In a large bowl, combine pork, cabbage, mushrooms, garlic, green onions, hoisin, ginger, sesame oil, Sriracha and white pepper.
To assemble the dumplings, place wrappers on a work surface.
Spoon 1 tablespoon of the pork mixture into the center of each wrapper. Using your finger, rub the edges of the wrappers with water. Fold the dough over the filling to create a half-moon shape, pinching the edges to seal.
Heat oil in a large skillet over medium heat.
Add wontons in a single layer and cook until golden and crisp, about 2-3 minutes per side.
When they are golden brown on both sides, add 1/3 cup chicken stock to the pan, turn the heat down to low, cover, and cook for another 2 minutes. This ensure the filling cooks completely.
Remove wontons with a spider, place on a heatproof platter and keep in the warm oven.
Clean the pan in between batches by pouring in water and allowing the pan to deglaze a bit. This will prevent your pan, and the wontons, from getting charred.
Repeat until all the wontons are cooked. Serve immediately.
Serve immediately with soy sauce, if desired.
To freeze, place uncooked wontons in a single layer on a baking sheet overnight, and place in your freezer. Once completely frozen, transfer to freezer bags. Freezing the wontons first prevents them from sticking together.
Let them thaw for about 10-15 minutes before cooking.