Add the egg, butter, butter, oat milk, and sugar to a mixing bowl. Mix on high for approximately 3 minutes, or until the sugar is dissolved and the mixture is a little foamy.
Add the rest of the ingredients to the bowl. Using a spatula fold in the ingredients until just incorporated.
Spray 2 donut pans with non stick spray.
Add equal amounts of the batter to the donut pans.
Bake for 15-20 minutes, or until golden brown.
Allow to sit for several minutes before removing from the pans.
Let donuts cool before glazing.
Churro Topping
Mix the sugar and cinnamon together.
Brush the tops of the donuts with the melted butter.
Dip the donuts into the cinnamon and sugar mixture.
If adding additional toppings, drizzle on melted chocolate, dulce de leche and/or top with a churro marshmallow.
Notes
These donuts are both gluten free and dairy free. Because I use Gluten Free 1.1 flour you can substitute this for regular AP flour. Additionally I use dairy free milk and butter in this recipe. Feel free to use dairy products, or experiment with different milk alternatives such as almond milk.