Cut tofu into bite-sized pieces.
Finely chop onion and bell pepper.
Heat olive oil in a pan and sauté onion and bell pepper.
Add tofu to the pan and stir-fry together.
Season with salt and pepper.
Place tofu and vegetables in an oven-safe dish.
Pour tomato sauce over and top with cheese.
Bake in a 180°C (356°F) oven for 10 minutes.