Lightly dust a large baking tray with flour. This is where you’ll place your dumplings once they’re filled.
Divide the dough into 4 equal portions and roll each into a ball. Leave 3 balls in the bowl and lay a piece of plastic wrap directly on top.
Flour your work surface where you’ll roll out the dough. Place 1 dough ball on the floured surface and roll it out with a floured rolling pin until it’s fairly thin.
You can use a round cookie cutter (about 2 1/2 inches in diameter) to stamp out circles. Alternatively, you can slice the dough into 2 1/2 inch squares; either use a knife with a ruler to guide you, or use a pizza cutter.
Place about 1 teaspoon of filling in the center of each piece of dough. Fold the dough over onto itself, and then pinch the outer edges together.
Put the Pelmeni onto the floured tray and dust with a little flour.
Spread the dumplings out evenly on the tray, trying not to let any of them touch.
Put the tray into the freezer until the Pelmeni is completely frozen, about 2 to 3 hours.
Once frozen, transfer the dumplings to a zip-top plastic bag. Label the bag with the date and contents, and freeze for up to 3 months.