Sauté the Aromatics: In a large skillet, heat 3 Tablespoons of vegetable oil on high heat. Add the diced onions and cook until translucent (2 minutes). Add the garlic and cook for 2 minutes, stirring frequently. Add the ginger and cook for 1 minute until fragrant.
Cook the Vegetables: Reduce heat to medium-high. Add the shiitake mushrooms, water chestnuts, Asian chives, Shao Xing wine, salt, sugar, and black pepper. Cook and stir for 7 minutes until the vegetables are soft.
Thicken and Cool: In a small bowl, whisk together the tapioca starch and water. Pour the slurry into the skillet, stirring constantly until the mixture thickens into a glossy gravy. Remove from heat, transfer to a bowl, and let the vegetables cool completely for 20 minutes.
Mix the Pork: In a large mixing bowl, add the raw ground pork and the cooled vegetable mixture. Knead thoroughly with your hands until well combined.
Fold the Dumplings: Place a dumpling wrapper in your palm and scoop 1 Tablespoon of filling into the center. Fold the bottom up to create a half-moon. (If your wrappers are dry, dab the edges with a little water so they stick together before folding). Place the dumpling on the counter, cup the filling to squeeze out air, and crimp the edges from right to left to seal. Press down lightly to flatten the bottom. Repeat with remaining wrappers.
Pan-Fry (Potsticker Method): Heat 1-2 Tablespoons of oil in a large non-stick pan over medium-high heat. Place dumplings flat-side down, ½-inch apart, and fry for 1 minute until lightly browned. Pour ½ cup of water into the pan, quickly cover with a lid, and reduce heat to medium. Steam for 5 minutes. Remove the lid and fry for a few final minutes until the water is gone and the bottoms are golden and crispy!