Cook the pasta in 3-4 l boiling salted water according to the instructions on the packet until al dente. In the meantime peel and finely dice the onion. Heat 1 tsp. oil in a pot. Fry the onion for about 2 minutes until transparent. Add tomatoes, bring to the boil and simmer for about 3 minutes.
Wash the fish, dab dry and cut into 4 pieces. Season fish with salt and pepper and turn in flour. Lightly tap off excess flour.
Stir the cream cheese into the tomato sauce and let it melt. Drain the pasta and let it drain, collecting 100 ml pasta water. Stir the pasta water into the sauce. Put the pasta back into the pot. Add the sauce and mix everything and season with salt and pepper.
Wash and chop the parsley. Heat 2 tablespoons of oil in a frying pan. Fry the fish for 2-3 minutes on each side, adding some chilli flakes and parsley. Arrange everything.