In a stand mixer, beat together 2 sticks of room-temperature unsalted butter and 1 cup of sugar until the mixture is light and fluffy, about 3-5 minutes. Add in 1 ½ teaspoons of peppermint extract, 1 teaspoon of vanilla extract, 1 teaspoon of baking powder, and ½ teaspoon of kosher salt, blending until smooth. Introduce 1 large egg, mixing well, then gradually add 2 ¾ cups of all-purpose flour until no dry streaks remain.

Once the dough is well combined, divide it in half. To one half, add 1 teaspoon of liquid red food coloring, mixing thoroughly until the color is uniform throughout. Wrap each portion tightly in plastic wrap and refrigerate for at least 3 hours, or preferably overnight, allowing the flavors to meld and the dough to firm up for easier handling.

Preheat your oven to 350°F (175°C) and line baking sheets with parchment paper. Retrieve the chilled dough, then roll out pieces from the white and red dough into 5-inch ropes. Gently twist them together to create the iconic candy cane shapes, placing them on the prepared baking sheets. Aim for a slightly curved appearance for that classic look.

In a small bowl, whisk the egg white until it becomes frothy. Carefully brush the shaped cookie ropes with the egg white; this will allow the sparkling sugar to adhere beautifully. After brushing, generously sprinkle the cookies with 2 tablespoons of sparkling sugar for a delightful crunch and festive sparkle.

Place your baking sheets in the preheated oven and bake the Flaky Candy Cane Cookies for 8-10 minutes, or until the edges are just starting to turn golden. Keep an eye on them to avoid over-baking; they should remain soft and inviting. Once baked, allow the cookies to cool on the sheet for 10 minutes before transferring them to a wire rack to finish cooling completely.