Peel the peaches by immersing them in boiling water for 1 minute. Remove with a slotted spoon and plunge into a bowl of ice water to cool slightly. Transfer to a cutting board. Remove the skins with a paring knife then slice. To prevent discoloration, treat with Fruit-Fresh® (an ascorbic acid–based product found in supermarkets) according to package directions. Lay the slices, slightly separated, on baking sheets lined with wax paper or parchment. Loosely cover with plastic wrap and place in the freezer until frozen, 1 1⁄2 to 2 hours. Peel the slices from the sheets and pack in heavy-duty plastic freezer bags, taking care to remove as much air as possible from the bag. Freeze for up to 1 year.