Peel and finely dice the onion and garlic. Heat clarified butter in a pot, fry onion and garlic over low heat until transparent. Add rice and sauté briefly. Season with salt, pepper and saffron.
Gradually add wine and stock, stirring from time to time. Always add the next portion of liquid only after the rice has absorbed the liquid. Cook for a total of 30-35 minutes.
Clean, wash and cut the peppers into strips. Wash and clean the mussels thoroughly. Discard opened mussels. Add peas, peppers and mussels to the risotto after about 15 minutes. Throw away closed mussels.
Arrange on plates. Sprinkle with parmesan.