Wash the bok choy thoroughly and cut it into bite-sized pieces.
Dice the tofu and slice the mushrooms (such as shiitake or button mushrooms).
Heat cooking oil in a pan and cook the tofu until golden brown.
Add the mushrooms and stir-fry, then add the bok choy and stir-fry together.
Season with soy sauce, minced garlic, and black pepper.
Serve the stir-fried mixture over rice and sprinkle with sesame seeds to finish.