Pat your tofu dry by placing the cubed tofu on a paper towel-lined plate for about 5 minutes. This helps it hold its shape while cooking.

Toast and grind your Sichuan peppercorns in a dry skillet over medium heat for about 60 seconds until fragrant, then crush with a mortar and pestle or the back of a spoon. Set aside.

Heat the oil in a large skillet or wok over medium-high heat. Add the ground beef and cook, breaking it up, until browned — about 5 minutes. Drain excess fat if needed but leave about a tablespoon in the pan.

Push the beef to the side and add the doubanjiang, fermented black beans, garlic, ginger, and green onion whites to the center of the pan. Fry in the oil for about 1–2 minutes until fragrant and the paste darkens slightly.

Mix everything together, then pour in the chicken broth, soy sauce, fish sauce, and sugar. Stir to combine and bring to a gentle simmer.

Gently slide in the tofu and spoon the sauce over the top. Simmer for 5 minutes without stirring too aggressively — you want the tofu to warm through and absorb the sauce, not crumble.

Stir in the cornstarch slurry and cook for another 1–2 minutes until the sauce thickens to a glossy consistency.

Finish with ground Sichuan peppercorn, a drizzle of sesame oil, chili oil if using, and the green onion tops. Serve immediately over steamed white rice.