Wash the red peppers, remove the inside and cut them into cubes.
Now, chop the onion and mash an unpeeled garlic. Fry the oil, an onion and a clove of garlic in a well-heated frying pan.
Brown, remove the garlic and add the red peppers, a little salt and a little black pepper and cook everything for about 15 minutes with the lid, until the pepper is flavoured but it also becomes crispy.
Add the diced tomatoes (preferably Corbarino tomatoes or cherry tomatoes) and cook for another 10 minutes, stirring everything.
Meanwhile, cook the fusilli in boiling salted water for 10 minutes. Then, drain the pasta and stir-fry it for a minute with the seasoning.