Heat oil in wok, place the tofu pieces in and then let them stay for 3-5 minutes until one side becomes slightly browned and hardened. Then turn over and fry the other side. Fry the tofu pieces until crispy and slightly browned on both sides. Transfer out.
If there are extra oil in the pan, discard extra oil and leave around 1 tablespoon of oil only. Fry chili peppers and Sichuan peppercorn with slow fire and then add ginger, garlic and red onion.
Fry until aromatic. Add pan-fried tofu, coriander, salt, sugar, chili powder and cumin powder. Quickly mix well and serve hot!