Preheat oven to 425 degrees. Coat a 6-donut pan with cooking spray.
In a small bowl, mix together the ground flaxseed and water to make the flax egg.
Use an electric mixer to cream the softened butter and cane sugar.
Beat in the vanilla, almond milk and flax egg.
Fold in the flours, cinnamon, salt and baking powder. Briskly stir together with a spatula.
Pour the batter into the donut pan. Bake for 17-20 minutes, or until the donuts are mostly firm and lightly browned on the bottoms.
Allow the donuts to cool for 10 minutes.
Meanwhile, mix the cinnamon + cane and brown sugars together. Transfer to a quart sized plastic bag.
Brush the tops of the donuts with the melted butter. One by one, carefully place a donut in the plastic bag and shake to coat the donut with the cinnamon sugar mixture. Enjoy!
Notes
*I only use 1/2 of the cinnamon sugar mixture, but I find it better to have a bit extra to shake up the donuts with.