Add dry ingredients to a medium mixing bowl and whisk together.
In a separate bowl, mix butter, egg and vanilla extract until creamy (about 30 seconds).
Pour dry ingredients into bowl of wet ingredients and stir with a spatula until well combined.
Cover bowl and chill in the fridge for 45 minutes.
While the dough is in the fridge preheat the oven to 340°F and prepare a cookie sheet with parchment paper or silicone baking mat.
Roll the cookie dough into balls, about 2 Tablespoons per cookie.
In a small bowl, stir together the stevia and cinnamon. Roll each dough ball in this cinnamon "sugar" mixture, until the surface is coated.
Flatten the balls a little with your hands and place them onto the prepared baking sheet, about 2 inches apart.
Bake for 10 to 12 minutes or until cookies are set around the edges but still soft in the center. (The cookies will set more after they cool).
Remove the baking sheet from the oven and let the cookies cool on the sheet for 4 to 5 minutes. Transfer to a wire cooling rack and cool completely.