Cover the dough with a towel and leave it in a warm place until doubled in volume. Make 1 large, or 2 medium pitas from the dough, and if desired, make lines along the length. Cover the pitas again and leave them for another 30 minutes.
Beat the egg yolk with 2 tablespoons water or oil and smear it on the lavash. Preheat the oven to 410°F (210 °C) and bake the bread for about 20 minutes until golden.