Preheat oven to 350F. In a medium-sized bowl, whisk together dry ingredients: flour, baking powder, baking soda, spices, and salt.
Grate the apple using the large holes of a box grater. Squeeze as much moisture from the grated apple as possible,
In a separate bowl, wish together the wet ingredients: grated apple, brown sugar, apple sauce, greek yogurt, egg, and vanilla.
Slowly whisk the wet ingredients into the dry until just fully combined.
Grease your donuts molds with cooking spray. Evenly divide batter between 9 donut molds or muffin tins. Mine came out to about 3 tbsp batter per mold.
Bake until just cooked through, when a tooth pick inserted comes out completely clean, about 12-18 minutes. Mine were perfectly done at 16 minutes. Let cool for about 5 minutes.
For the coating, mix together the remaining sugar and cinnamon.
Once donuts are cooled, remove from donut pan and spray lightly on all sides with cooking spray. Dip the slightly moist donuts, one at a time, into the sugar coating just before serving.*