In a large bowl, mix the ground pork with the ginger, shallot, garlic and ground Szechwan peppercorns. Stir in 2 tablespoons of the rice wine and the sugar, 1/2 teaspoon of salt and sesame oil. Form the mixture into 10 meatballs.
In a large, heavy saucepan, heat the vegetable oil until shimmering. Add the meatballs and cook over moderately high heat until browned all over, about 4 minutes.
Add the chicken broth and mushrooms and simmer over moderate heat until the meatballs are cooked through, about 10 minutes. Add the spinach, scallions, soy sauce and the remaining 3 tablespoons plus 1 teaspoon rice wine and simmer until the spinach is just wilted, about 1 minute. Season the soup with salt and serve with chili sauce on the side.