1 1/2 cups (210 g) all purpose gluten free flour (I used Better Batter), plus more for sprinkling
3/4 teaspoon xanthan gum (omit if your blend already contains it)
2 tablespoons (18 g) cornstarch
1 teaspoon baking powder
1/4 teaspoon kosher salt
1/2 cup (100 g) granulated sugar
1/2 cup (100 g) finely crushed peppermint candy canes (or starlight mint hard candies)
2 eggs (100 g, weighed out of shell) at room temperature, beaten
2 teaspoons pure vanilla extract
1 teaspoon peppermint extract
White chocolate, melted, for drizzling (optional)
Preheat your oven to 350°F. Line a rimmed baking sheet with unbleached parchment paper and set it aside. If you haven’t already crushed the candy canes or peppermint Starlight mints, place them in a heavy duty zip-top bag, cover with a cotton tea towel, and crush them using a meat tenderizer or mallet.
In a large bowl, place the flour, xanthan gum, cornstarch, baking powder, salt and sugar, and whisk to combine well. Add the crushed candies, and whisk again to combine. Add the eggs, vanilla extract, and peppermint extract, and mix to combine well. The dough will be thick and very sticky. Sprinkle your hands with additional flour and knead the dough lightly with your hands until a bit smoother. Divide the dough into two equal portions, and, with lightly floured hands, shape each into a loaf that is about 3 1/2-inches long x 3-inches wide x 1-inch thick. Place the loaves about 4 inches apart on the prepared baking sheet.
Place the baking sheet in the center of the preheated oven and bake until lightly golden brown and firm to the touch, about 25 minutes. Remove from the oven and allow the loaf to cool for at least 10 minutes, or until only slightly warm to the touch. For easier slicing, place the loaves in the freezer for 10 minutes. Lower the oven temperature to 300°F.
Using a large serrated bread knife, slice each loaf in cross-section on the bias into 5 to 6 pieces, each about 1/4 inch thick. Place the pieces, one flat side down, back on the prepared baking sheet, spaced about 1 inch apart. Return the baking sheet to the oven and bake for 10 minutes. Working quickly with a light touch, flip each of the cookies over on the baking sheet. Return the baking sheet to the oven one last time and finish baking until the underside of the cookies is lightly golden brown (about another 10 minutes – less if you want less crunchy cookies). Remove from the oven and allow to cool to room temperature. The cookies will crisp as they cool.
Drizzle the cooled cookies with the melted white chocolate, if using, and allow the chocolate to set at room temperature. Store leftover cookies in a sealed glass container at room temperature to maintain crispness.