Cut the zucchini into slices, dice the bell pepper. Melt half of the butter, sweat the onion and garlic in it until lightly. Add the vegetables and cook for about 5 minutes. Pour in the cream, season and heat to boiling point. In the meantime, cook the macaroni or spaghetti in salted water until al dente, drain and mix immediately with the remaining butter, vegetables and cheese. Serve immediately.