Roast the walnuts in a pan without fat for about 5 minutes while stirring.

Wash the parsley and shake dry. Finely grate the mountain cheese. Coarsely puree the walnuts, cheese, garlic clove (was soaked in olive oil) and olive oil. Season to taste with salt and pepper.

Meanwhile cook the pasta in boiling salted water according to the instructions on the packet. Drain, collecting about 50 ml of pasta water. Mix pasta, pesto and pasta water. Spread on plates and serve with a few walnuts sprinkled with some mountain cheese.