Preheat oven to 350 degrees. Line 2 large baking sheets with parchment paper
In a medium mixing bowl whisk together almond flour, vital wheat gluten. tapioca flour, salt, baking powder, and cream of tartar until fully combined.
In a large mixer bowl beat Softened butter and powdered Swerve on low for 1 minute of until creamy.
Add egg yolks and vanilla. Beat on low 1 more minute or until light and fluffy.
Add dry ingredients to wet ingredients and beat on low 30 seconds or until no dry ingredients are left in the bowl.
Scrape all ingredients to the center of the bowl. Lightly cover the bowl with plastic wrap and place in the refrigerator for at least 1 hour.
Remove dough from refrigerator and place dough onto lightly floured work surface
Press or roll dough out to 1/2-1/4 inch thick. Place onto prepared baking sheet and bake 8-10 minutes or until the edges are lightly brown.
Let cookies cool on the pan for 5 minutes then transfer to a wire rack to cool completely.
Cookies will be soft at first but they will firm up as they cool. Let cookies cool completely before frosting.