Cook the spaghetti in salted water with a dash of oil until al dente. Drain and quench. Drain well.
For the sauce, cut the peppers in half, remove the stones and white skins, wash the flesh and cut very finely. Peel and finely dice the garlic. Briefly hold the parsley under water, pluck the leaves off and cut them into small pieces.
Heat the olive oil in a pan and briefly fry the peppers and garlic. Add the spaghetti, mix in and let it get hot. Mix in the parsley, sprinkle everything with the parmesan and serve immediately.