Penne with walnuts and salmon

Preparation:

Preparation: Fry a finely chopped onion with a coarser one of walnuts and pistachios in a few tablespoons of oil. After a few minutes add a drop of cognac and let it evaporate, then add the salmon cut into strips and a grind of fresh pepper; leave it to flavor for a few more moments then switch off. In a bowl, mix the egg yolk with a few tablespoons of oil and a pinch of salt; pour over the al dente drained pasta and season with the sauce, mixing carefully before serving. A variant of the recipe uses a quart of fresh cream instead of the egg.