Cut the soft tofu into bite-sized pieces.
Finely chop the Cheongyang chili pepper and green onion.
Mince the garlic.
Mix together soy sauce, water, minced garlic, chili pepper, and green onion to make the sauce.
Place the sliced soft tofu in an airtight container and pour the sauce over it.
Let it marinate in the refrigerator for at least 1 hour before serving.