Remove pie crusts from pouches; unroll on lightly floured surface. Using 3-inch round cookie cutter, cut 12 rounds from each crust. On cookie sheet, place 12 of the dough rounds. Brush dough with half of the beaten egg. Spoon about 1 tablespoon apple mixture on each round to within 1/2 inch of edge; top each with 1 cube of butter. Top pies with remaining 12 dough rounds; press edges together with fork to seal. Brush with remaining beaten egg.