Combine ground lamb meat, Shaoxing wine, light soy sauce, and dark soy sauce in a large bowl. Mix well until the mixture becomes a sticky paste. Add ginger. Sprinkle evenly with Sichuan peppercorn powder and salt (if you’re using it). Mix thoroughly. Add peanut oil and mix well. Cover with plastic wrap and set aside (or in the fridge if you’re not planning to make dumplings within an hour).