01 - Preheat oven to 350°F. Line a baking sheet with parchment paper.
02 - In a large bowl, beat together butter and powdered erythritol until light and fluffy.
03 - Add egg, lemon zest, lemon juice, and vanilla extract. Mix until combined.
04 - In a separate bowl, whisk together almond flour, coconut flour, baking powder, and salt.
05 - Gradually add dry ingredients to the wet ingredients, mixing until a soft dough forms.
06 - Scoop tablespoon-sized portions onto the prepared baking sheet. Flatten gently with your hand or the back of a spoon.
07 - Bake for 10-12 minutes, until edges are lightly golden. Cool completely on a wire rack.
08 - Beat together powdered erythritol, cream cheese, butter, lemon juice, and heavy cream until smooth.
09 - Spread or drizzle glaze over cooled cookies. Garnish with lemon zest if desired.
10 - Allow glaze to set before serving.