Mix 2 tablespoons of ground flaxseed with 6 tablespoons of water and let it sit for about 5-10 minutes until it thickens.
In your mixer, cream together the vegan butter, granulated sugar, and brown sugar for at least 4 minutes until light and fluffy. Scrape down the sides of the bowl as needed.
Add the vanilla extract and mix until combined. Then, add the prepared flax eggs and mix again until fully incorporated.
In a separate bowl, whisk together the flour, baking soda, salt, and cream of tartar.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Be careful not to overmix. If the dough is too wet, add a couple of tablespoons of flour. If it’s too dry, add a splash of plant milk.
Weigh out the cookie dough into 3-ounce balls and roll each ball in the cinnamon-sugar mixture until fully coated.
Refrigerate the dough balls for at least 30 minutes to help the cookies maintain their shape while baking.
Preheat your oven to 375°F (190°C).
Optionally, do a test bake with one cookie to ensure your oven does not run hot.
Bake the cookies for 18-20 minutes, turning them halfway through. The cookies should have a matte finish on top when done.
Let the cookies set for 30-45 minutes to firm up before enjoying.