Gently place tofu cubes in a pot of hot salted water and let them soak for 10 minutes to warm through and firm up. Drain carefully.

Heat vegetable oil in a wok over medium heat. Add Sichuan peppercorns and fry for 1 minute until fragrant, then remove and discard the peppercorns.

Add ground pork to the wok, breaking it apart, and cook until no longer pink, about 3 minutes. Push the pork to one side, add doubanjiang and fermented black beans, and stir-fry for 1 minute until the oil turns red and fragrant.

Add garlic, ginger, and scallion whites. Stir for 30 seconds. Pour in the chicken broth, soy sauce, and sugar. Bring to a simmer.

Gently slide the drained tofu into the sauce. Simmer covered over medium-low heat for 8-10 minutes, gently stirring once or twice to avoid breaking the tofu.

Drizzle in the cornstarch slurry and gently stir until the sauce thickens. Finish with chili oil and ground Sichuan peppercorn. Garnish with scallion greens and serve with steamed rice.