01 - Preheat the oven to 350°F (175°C) and line a baking sheet with parchment paper.
02 - Whisk together almond flour, coconut flour, erythritol, baking powder, and sea salt in a medium bowl.
03 - Cream softened butter until smooth, then beat in the egg, sugar-free maple syrup, vanilla extract, and maple extract if using.
04 - Add the dry ingredients to the wet mixture and stir until a soft dough forms.
05 - Scoop tablespoon-sized portions of dough onto the prepared baking sheet, spacing them about 2 inches apart, then flatten slightly with fingers or a spoon.
06 - Sprinkle chopped pecans or walnuts and a pinch of flaky sea salt on each cookie, if desired.
07 - Bake the cookies for 10–12 minutes, until edges are just golden.
08 - Allow cookies to cool on the baking sheet for 10 minutes, then transfer to a wire rack to cool completely.