01 - Preheat the oven to 350°F. Line a baking sheet with parchment paper.
02 - In a medium bowl, whisk together almond flour, coconut flour, erythritol, baking powder, and salt.
03 - In a large bowl, beat the softened butter, egg, vanilla extract, and peppermint extract until smooth and creamy.
04 - Gradually add the dry ingredients to the wet mixture, stirring until a soft dough forms.
05 - In a microwave-safe bowl, melt chocolate chips with coconut oil in 20-second intervals, stirring until smooth.
06 - Drizzle the melted chocolate over the dough and gently swirl with a spatula to create a marbled effect without overmixing.
07 - Scoop tablespoon-sized portions onto the prepared baking sheet, spacing 2 inches apart.
08 - If desired, sprinkle crushed sugar-free peppermint candies over the dough portions.
09 - Bake for 12 to 15 minutes, until the edges are just golden.
10 - Allow cookies to cool on the baking sheet for 10 minutes before transferring to a wire rack to cool completely.