Preheat the oven to 400°F and lightly grease a mini doughnut pan.
Sift the gluten-flour, xanthan gum, baking powder and salt together.
In a separate bowl, whisk together the melted coconut oil, almond milk, sugar substitute, vanilla, and egg. Add the egg mixture to the flour mixture and stir until just combined.
Fill each doughnut cup 3/4 of the way full with the batter. Fill with a spoon carefully. Bake until the doughnuts spring back when touched about 10 minutes. Let cool completely on a wire rack.
Ground the xylitol in a coffee grinder and place in a sturdy ziplock bag. Add the cinnamon and mix well. Once the doughnuts are slight cooled, add one doughnut at a time, and dust with the cinnamon powdered sugar.