01 - Preheat oven to 350°F and line a baking sheet with parchment paper.
02 - Whisk almond flour, coconut flour, baking powder, and salt together in a medium bowl.
03 - Beat softened butter and erythritol in a large bowl until light and fluffy.
04 - Add egg, vanilla extract, and caramel syrup to the butter mixture and blend thoroughly.
05 - Gradually add dry ingredients to wet mixture, stirring until a soft dough forms.
06 - Scoop tablespoon-sized portions onto prepared sheet spacing 2 inches apart and gently flatten each mound.
07 - Bake for 10 to 12 minutes until edges are golden; cool completely on wire rack.
08 - Beat butter and cream cheese until smooth, then add powdered erythritol, caramel syrup, and vanilla extract. Mix to creamy consistency, adding heavy cream as necessary.
09 - Spread or pipe frosting on cooled cookies and allow to set before serving.