Preheat your oven to 350°F and spray a baking dish with cooking spray. Dust a clean surface with flour and roll out the pie dough to about 1/8 inch thick.

Cut circles out of the rolled dough using a round cookie cutter, about 2 3/4 inches in diameter. Gather and reroll any leftover scraps.

In a mixing bowl, combine apple, blueberry, cherry, and cranberry fillings, stirring gently. Adjust sweetness as needed.

Place a tablespoon of filling in the center of each dough round, fold over, and press edges together to seal. Crimp with a fork.

Whisk the egg and brush a light coat over the dough tops for a glossy finish.

Arrange filled dough halves in the baking dish and bake for about 45 minutes, until golden brown.

Allow to cool for 10 minutes before serving warm.