In a pot with boiling water (optionally add a piece of onion, garlic and salt to season it), add pasta and cook over medium heat until tender (approximately 10-15 minutes). Remove from heat, pour into a colander and rinse the pasta with clean water (if you added onion and garlic, remove them). Reserve.
In a pan over medium heat, add oil and let it heat up. Once hot, add garlic, onion and bell pepper. Sauté until they start to brown and look slightly roasted (about 15 minutes).
Preheat the oven to 180°C (360°F) for 15 minutes.
Transfer the garlic, onion and peppers to a blender, add tofu, nutritional yeast, salt and pepper. Blend until you get a creamy sauce.
In a large bowl, mix the previously cooked pasta with the sauce. Pour into an oven safe mold, add the cheese on top and bake for 20-25 minutes or until the cheese slightly browns.