Whisk soy sauce, vinegar, sugar, salt, and water into a sauce mixture.
Heat oil in a wok, stir-fry peanuts until golden brown; remove and set aside.
In the same wok, pan-fry cubed tofu coated in cornstarch until crisp; set aside.
Sauté dry red chilies, ginger paste, and garlic paste for 1 minute, then add crispy tofu and roasted peanuts.
Pour in the sauce, cook until thickened and glossy, and toss with chopped spring onions before serving.