Heat vegetable oil in a frying pan. Pour some of the egg mixture to make a thin pancake.
Put some of the filling on half of the pancake.
Then close the filling with the second half of the pancake. If necessary, grease the empty part of the pan with oil and add some egg mixture again to make a thin pancake again. Put some of the filling on it. Flip the thick omelet onto the freshly poured pancake. Continue to form layers of omelet until the egg mixture is finished