Preheat your oven to 350°F (175°C). Line a baking sheet with parchment paper or use a silicone baking mat.

In a medium bowl, whisk together almond flour, coconut flour, xanthan gum, baking soda, cream of tartar, and salt.

In a separate large bowl, use an electric mixer to cream the butter and 6 tablespoons of allulose until light and fluffy.

Beat in the egg and vanilla extract until well combined.

Gradually add the dry ingredients to the wet mixture, mixing until a dough forms. The dough should be thick but manageable.

In a small bowl, mix the remaining 2 tablespoons of allulose with the cinnamon.

Scoop about 1 tablespoon of dough and roll into a ball. Roll each ball thoroughly in the cinnamon-allulose mixture to coat. Place on the prepared baking sheet, spacing about 2 inches apart. Lightly flatten each ball with your palm or the bottom of a glass.

Bake for 10-12 minutes or until the edges are lightly golden. They will appear slightly underdone but will firm up as they cool.

Let the cookies cool on the baking sheet for about 5 minutes before transferring to a wire rack to cool completely.