1. Cook the pasta in a large pot of boiling water, adding oil.
2. Meanwhile, slice the sausages.
3. Finely chop the onion.
4. In a skillet, sauté the onion in oil for 2-3 minutes until translucent.
5. Add the sausage slices and cook for another 2-3 minutes over low heat.
6. Then, take 65 ml of pasta cooking water and add it to the skillet along with salt and pepper.
7. Keep warm over very low heat.
8. When the pasta is cooked, drain it and add it to the skillet.
9. Mix well and adjust the seasoning if necessary.
10. Serve hot, garnished with chopped parsley.