Cook the spaghetti in salted water according to the instructions on the packet and drain.
Meanwhile prepare the vegetables and cut them into small pieces.
Fry the onions in olive oil until translucent, then add the garlic, add the paprika and zucchini and cook everything on a low heat. Add the drained tuna and season with salt, pepper and the chopped chilli pepper. Finally stir in the crème fraîche and season again to taste.
Pour the tuna sauce over the cooked noodles and serve.