Cut the soft tofu into bite-sized pieces.
Finely chop the onion, garlic, and bell pepper.
Heat olive oil in a pan and sauté the onion, garlic, and bell pepper.
Add tomato sauce and simmer.
Add the soft tofu and season to taste.
Transfer to an oven-safe dish and top with mozzarella cheese.
Bake in a preheated oven at 180°C for 10 minutes.