Pre-heat the oven at 200°C (fan mode). Spread the filling evenly over the dough,
leaving about 5 cm of edge on one side, then roll into a loose roll, place on a baking
tray which you have sprinkled abundantly with flour or covered with baking paper. Brush
the edge with egg white, then gently fold over. Mix the egg yolk with a bit of water and
brush the mixture all over the surface of the pierogi. Bake for about 30 minutes or
until golden:
