Put to boil water and the oil, add the baking soda and salt. Pull the container from heat and immediately add the flour, stirring continuously. Flour not certain amount - put it so that the dough can be sharpening. Divide dough in half. Roll out one half of the crust and put it in a pan greased with butter. Spread evenly over the top layer of pre-fried meat with the onion, the oil and pepper. Roll out the second crust and place it over the meat. Prick the banitsa with fork and then bake in moderate oven. Serve it warm by.