Add the oat flour, rolled oats, baking powder, baking soda, salt, cinnamon, nutmeg, and sweetener to a large bowl. Thoroughly mix these dry ingredients.

Peel the bananas and add them to a separate bowl. Thoroughly mash the bananas with a fork or potato masher. Add the eggs, applesauce, and vanilla extract to the bowl and whisk until the wet ingredients are combined.

Add the wet ingredients to the bowl with the dry ingredients a little at a time, until fully incorporated, making sure not to over-mix.

You can leave the fresh cranberries whole, lightly pulse them using a food processor or blender, or roughly chop them on a cutting board. Lightly fold the cranberries into the batter.

Lightly spray a non-stick muffin pan with oil or add parchment muffin liners. Then, use an ice cream scoop or measuring cup to pour the batter into the muffin cups.

Bake the muffins at 350°F for 18-22 minutes, or until a toothpick inserted in the center comes out clean. Once done, let the muffins slightly cool, and enjoy!