Add remaining ingredients and blend for another 30-40 seconds.
Place 3 large silicone muffin cups on a baking sheet, and fill evenly with batter.
Bake at 325F (163C) for about 30 minutes, until they are firm to the touch and a toothpick comes out clean.
Enjoy!
Notes
A note about substitutions: because each type of protein powder has a distinct flavor and texture when baked, I would not try substituting different types of protein powders in this recipe. You can, however, substitute 1 cup of unsweetened applesauce for the apples in this recipe.Also note that some of the cinnamon flavor is lost during baking, so if your batter tastes perfect, add a little more cinnamon.