Preheat oven to 400°F. Spray mini donut pan with cooking spray.
In a large bowl, whisk together flour, baking powder, baking soda, salt, and cinnamon.
In another bowl, whisk together egg, brown sugar, applesauce, agave nectar, cider, yogurt, and oil.
Add in dry ingredients and stir until combined.
Fill each mini donut halfway. Bake for 10 to 12 minutes. Let donuts cool slightly for a few minutes. Use a plastic knife, gently pry around edges of the donut until donuts pop out.
Let donuts cool completely. Then melt 1/4 cup butter in a small glass bowl. In another small bowl, combine 2/3 cup white sugar and 2 tsp cinnamon. Dip top of donuts in melted butter and then dip in the sugar mixture.
The nutrition information provided are only estimates based on an online nutritional calculator. This is not a comprehensive list of all the nutrients in the recipe (i.e., does not include vitamins, cholesterol, etc). I am not a certified nutritionist. Please consult a nutritionist or doctor for accurate information and any dietary restrictions and concerns you may have.