Peel and steam the potatoes, then chop into small cubes. Add potato with chopped nuts and grated pecorino. Mix everything together adding a pinch of salt and pepper.
With a pasta machine, roll out the dough into long strips, about 6 cm.
Arrange a little every 6-7 cm 'of filling in the middle of the strip of dough, cover with another strip of dough, press with your fingers around each mound of filling to release any air bubbles. Cut out the "medallions" with the appropriate tool.
Prepare the sauce: In a pan, melt the butter, then sauté the breadcrumbs and nuts, then add the chopped parsley. In a saucepan, bring to a boil the water, add salt, pour the "medallions" and cook for 6-7 minutes. Drain and season. Sprinkle with grated Parmesan cheese and serve hot.
Great pasta stuffed, doughy consistency within and outside grainy. The delicate flavor of potatoes goes well with the deep shades of nuts. Cheese, pepper and parsley enhance the taste of this dish really appetizing.