Mix flour, egg, oil and a little water to a firm dough and add salt. Let the dough rest for about 1 hour. In the meantime, peel and chop the onion.
Clean the leek thoroughly, wash, drain and cut into thin rings. Heat the oil in a pan and brown the onion and leek well.
Add the minced meat and brown. Remove the pan from the heat, add the egg whites and breadcrumbs to the mixture in the pan, mix and season. Roll out the dough thinly on a floured work surface and cut out circles with a glass or cookie cutter.
Put some filling on the dough and fold the dough in a semicircle to form small pockets. Press the edges well and press prongs into them with a fork.
Cook the pasta in boiling salted water for about 15 minutes. Serve with melted butter or melted bacon.
