To make the hot dressing, heat the olive oil in a frying pan and when hot add the onions, garlic, anchovies, capers, rosemary and parsley. Fry gently until the onions have softened, without colouring them. Keep warm until ready to serve.
Meanwhile, cook the broccoli in plenty of boiling water with a little salt for two minutes, then add the fettuccine and stir and cook for another three minutes. Drain when the pasta is cooked (the broccoli will have broken up slightly).
To serve, place the pasta and broccoli in a bowl and combine with the hot dressing. Add lemon juice and season to taste with salt and pepper. Serve with shavings of parmesan.