Cut tofu into squares of about 1.5cm/ 0.5inch thick. Pad each piece dry with a clean tea towel or kitchen paper. Sift corn starch over tofu to create a thin coating (both sides).
Fry the tofu
Heat up 2 tablespoons of cooking oil in a wok (or a frying pan) over high heat. When the oil is hot, carefully place the tofu squares into the pan (Do not overlap. You might have to fry them in 2 batches).
Turn the heat down to medium. When one side becomes golden brown, flip over to cook the other side. Transfer onto a plate when both sides are done.
Cook the sauce
While waiting for the tofu to cook, mix Shaoxing rice wine, black rice vinegar, water, sugar and corn starch. Set aside.
Add 1 tablespoon of cooking oil into the same wok. Stir fry ginger, garlic, fresh chilli & Sichuan chilli bean paste until fragrant.
Pour in the liquid mixture (remember to stir well beforehand).
Assemble the dish:
Place tofu squares back into the wok. Gently move them around. Dish out when the sauce becomes thick and the tofu is evenly coated.
Garnish with scallions. Serve immediately with plain rice.