Grease a 9- x 13-inch baking pan or other jelly roll pan

Place half cup of cold water in the mixing bowl for a stand mixer and sprinkle gelatin over the water. Don’t dump gelatin as this will cause dry spots and clumps. Set aside.

Simmer three-quarter cup of water, granulated sugar, and cane syrup or corn syrup over medium heat. Cover the pan for 2 minutes once the mixture is at a boil so the steam can wash the sides and prevent crystallization.

Continue boiling until a candy thermometer, clipped to the side of the saucepan, registers 247°F to 250°F (firm ball stage). Turn off the heat.

With the mixer on low, pour hot sugar syrup onto bloomed gelatin. Drape a towel over the front of the mixer as you increase the speed to high, to prevent splatters. Once the mixture has started to thicken, you can remove the towel.

Continue whipping for about 10 minutes or until the mixture resembles thick soft serve ice cream and the bottom of the mixing bowl is cool to the touch. Add crushed peppermint candies, gel food coloring, and peppermint extract (if using), and mix just until you see red and white stripes. (Do not over mix or the whole batch will be red!)

Scrape marshmallow mixture into the prepared pan and spread evenly with your hands (lightly grease your hands so the marshmallows don’t stick) or a greased spatula.

Combine powdered sugar and cornstarch in a bowl and lightly sprinkle on top of marshmallows. Reserve remaining powdered sugar mixture for cutting marshmallows. Allow marshmallows to sit uncovered for at least 6 hours or overnight.

Cut marshmallows using a knife, pizza cutter, or cookie cutter dipped in powdered sugar mix. Toss each marshmallow to coat in powdered sugar mix and store at room temperature in a covered container for up to 2 weeks.