Preheat the oven to 350°F and lightly grease a donut pan.
Add the flour, baking soda, baking powder, cinnamon, nutmeg, and salt to a medium bowl. Whisk together and set aside.
In a large bowl, mash the bananas until mostly smooth.
Add the applesauce, sugar, vegetable oil, almond milk, and vanilla to the mashed bananas. Whisk until everything is well combined.
Add the dry ingredients to the wet ingredients and mix just until combined. Be careful not to overmix the batter.
Spoon or pipe the batter evenly into the prepared donut pan.
Bake at 350°F for 15 minutes.
Remove the donuts from the oven and let them cool before removing them from the pan.
Mix the sugar and cinnamon together in a small bowl.
Once the donuts are cool, dust the tops with the cinnamon sugar mixture and serve.