Wash, peel and thinly slice the potatoes. Cook the potato slices in boiling salted water for about 8 minutes. Also cook the pasta in salted water. Drain the potatoes and pasta, rinse in cold water and drain well. Coarsely grate the cheese.
Layer the potatoes, pasta and cheese in a greased baking dish. Bake in a preheated oven at 180 ° C top / bottom heat for about 15 minutes while being watched until golden brown.
Peel the onions, cut into slices and brown in the hot fat while stirring for about 5 minutes. Wash the parsley, pat dry and pluck the leaves from the stems.
Serve the cheese noodles with the browned onions and parsley leaves.