Cook the pasta in 3-4 l boiling salted water (approx. 1 teaspoon salt per litre) according to the instructions on the packet. Peel and finely chop the onions. Peel garlic and chop very finely. Wash lemon hot, dab dry and finely grate peel.
Squeeze the lemon. Wash the rosemary, shake dry and remove the needles. Pour sardines into a sieve and drain. Clean, wash and coarsely grate the zucchini.
Pour the noodles into a sieve, drain. Heat the oil in the pasta pot. Brown onions and garlic in it. Fry rosemary and lemon peel briefly. Season with salt and pepper. Add lemon juice and heat up.
Put the pasta back in the pot. Mix everything and heat up briefly. Cut half of the sardines into large pieces, fold in. Season to taste with salt and pepper and serve. Arrange the remaining sardines on top.
Serve sprinkled with zucchini shavings and pepper. Possibly garnish with lemon wedges.