Prepare the dough with the flour, egg yolks, melted butter or fat, sugar, yeast, salt and a little milk.
Prepare the filling by mixing the minced meat with the onion, hard-boiled egg and pepper.
Shape the dough into circles and half-moons as shown, filling each with the meat mixture.
Moisten the edges with water and press the halves together to seal, pressing firmly so they don't open while frying.
Fry the piroshki in 1/4 l oil.