Separate the perogie dough into two balls. Roll out one piece at a time on a lightly floured surface until it is thin enough to work with, but not too thin so that it tears. Cut into circles using a cookie cutter, perogie cutter, or a glass. Brush a little water around the edges of the circles, and spoon some filling into the center. Fold the circles over into half-circles, and press to seal the edges. Place perogies on a cookie sheet, and freeze. Once frozen, transfer to freezer storage bags or containers.