In a small skillet, toast the Sichuan peppercorns over high heat until fragrant, about 30 seconds. Transfer to a spice grinder and let cool completely. Grind the peppercorns to a coarse powder.
In a small bowl, mix the wine, light soy sauce, sesame oil, cornstarch slurry, sugar and ground peppercorns. In a medium bowl, mix the pork with the dark soy sauce.
In a large skillet, heat the vegetable oil. Add the pork and cook over moderate heat, breaking up the meat with a wooden spoon, until the meat is cooked throughout, about 5 minutes. Stir in the scallions and crushed red pepper and cook over moderately high heat for 2 minutes. Stir the sauce well, then add it to the pork. Stir-fry until simmering and thick, about 3 minutes. Reduce the heat to low and carefully fold in the tofu. Simmer very gently until the tofu is hot, about 3 minutes. Serve over rice.
The Sichuan peppercorn sauce and soy-dressed pork can be refrigerated, separately, overnight.