Preheat your oven to 425°F.
In a medium mixing bowl, whisk together all dry ingredients until well combined. Set aside.
2 ½ cups flour, 1 tsp baking powder, 1 tsp baking soda, 2 tsp ground cinnamon, ½ tsp salt, ½ cup white granulated sugar, ½ cup light brown sugar
In a separate mixing bowl, whisk together your wet ingredients.
1 ½ cups sweetened cinnamon applesauce, 2 eggs, ½ cup avocado oil, 1 tsp vanilla extract, ¼ cup sour cream
Add the dry ingredients to the wet ingredients about 1/2 - 1 cup at a time, stirring together until just combined. Do NOT overmix the batter as this can result in tough, rubbery muffins.
Place tall parchment liners in every other cup of a regular cupcake tin. I like to nest two wrappers inside each other to give the wrapper more structure and for aesthetic purposes. Spray the inside of the liners with the cooking spray of your choice (I prefer to use an avocado oil spray).
Fill each parchment wrapper ¾ of the way full, which is approximately 5 scoops when using a 1 ½" diameter cookie scoop or approximately 5.5 ounces of batter.
Bake the muffins for 5 minutes at 425°F. Then lower the heat to 400°F WITHOUT opening the oven door. Bake the muffins for 7 minutes at 400°F. Then turn the pan to ensure all muffins bake evenly. Bake for another 12 minutes at 400°F for a total bake time of 24 minutes. (See Note 4 below) The muffins should be golden brown and slightly cracked on top when they are done. A toothpick should come out clean when inserted into the center (a bit of crumb is okay). Let the muffins sit in the pan for 1-2 minutes before moving them to a cooling rack. While they cool, mix up your maple glaze.