The well-known New York Jewish delicacy - knish is a small dough pie filled with meat, potatoes or cheese. Sold on the streets of New York by vendors or in knosheries. In Russia and Eastern Europe the knishes were smaller than the New York version, which has grown to the size of a tennis ball. In France the knish is known in its Russian name, piroshki, and it is known in Yiddish as bagelah.
Knish dough recipe
Beat eggs with salt, baking powder, and oil. Add the flour gradually till dough is soft and unsticky. Knead dough until very smooth. If necessary, add flour. Coat dough with oil, cover the bowl and leave for an hour. Roll out as thin as possible and cut into rounds 3 inches in diameter. Stretch the dough again if it contracts and place 1 tbsp of filling in the center. Fold over, pinch the edges together firmly and place on baking sheets, making sure they are well-greased. Brush with egg yolk, bake in 350ºF for 20‑25 minutes, or until golden. Serve hot.
For the filling you can use onions, oil, ground beef, parsley and spices - all gently fried on a pan till half cooked. You can also fill with cheese or whatever other filling comes to mind, best liked with smoked salmon.