Line an 8-X 8-inch pan with two-inch sides with parchment paper. The paper should go up the sides as well as cover the bottom of the pan. Spray parchment paper with nonstick cooking spray. Set aside.

In a heavy stainless-steel saucepot, make simple syrup. Combine sugar, corn syrup and ½ cup plus 2 tablespoons water. Avoid using an aluminum pan, as the sugar may crystallize on the sides of the pan. Using a candy thermometer, heat on medium-high until the mixture reaches a temperature of 238 degrees. While syrup is heating, place gelatin and ¼ cup plus 2 tablespoons cold water in the bowl of an electric stand mixer.

Using mixer’s whisk attachment and with mixer on medium speed, carefully pour the hot syrup into the gelatin mixture. Add peppermint extract. Increase speed to medium high. Beat until mixture becomes white, thick and fluffy, about 12-to 14-minutes.

Spray a plastic spatula with nonstick cooking spray. Using the spatula, scrape mixture into the prepared pan. Press lightly to smooth out. If desired, use the tip of a toothpick dipped in red food coloring to make streaks on top of the marshmallows. Dust top liberally with powdered sugar. Let marshmallows cool in pan for 2 hours.

Place a large piece of parchment paper on a work surface. Sprinkle paper liberally with powdered sugar. Take sides of the pan parchment paper and lift marshmallows out of pan. Spray a knife with nonstock cooking spray. Cut marshmallows into squares. Roll the cut sides of the marshmallows into more confectioners’ sugar. Store at room temperature in a covered container, putting pieces of parchment or wax paper between the layers of marshmallows to avoid having them stick together. The marshmallows will keep for one week at room temperature or frozen for one month.

Leftover marshmallows can be stored in the freezer for up to one month. Place marshmallows in a freezerproof container, separating layers with wax or parchment paper.