Peel the apples and cut into strips. Sprinkle with lemon juice to prevent browning.
Preheat oven to 210°C (th. 7).
Divide the dough in half.
Roll out one half into a 15 cm x 30 cm rectangle. Place on a damp baking sheet. Arrange apple slices on top, 1 cm from edges. Brush with apricot jam.
Roll out the remaining dough to same size. Use a pastry wheel for 1 cm-spaced notches, stopping 1 cm from edge. Brush first crust's edges with egg yolk diluted in water.
Lay second sheet over, press edges to seal.
Brown surface with remaining yolk mixture. Bake 25-30 minutes until golden.
Serve warm or cold for a flaky, irresistible treat.
