1. Preheat oven to 350 degrees Fahrenheit (175 degrees Celsius). Line 22–24 muffin cups with paper liners and set aside.
2. To prepare batter with a food processor: In the bowl of a food processor fitted with an S blade, beat egg whites until stiff. Add ripe bananas and process for at least three minutes until a creamy, fluffy batter forms. (The longer you mix the bananas with the eggs, the fluffier your muffins will be.) Add egg yolks, vanilla extract, baking soda, nut butter, and Rorie’s Grain Free Flour Blend and mix well.
3. To prepare batter with an electric mixer: Mash bananas until creamy and lump-free. In the bowl of an electric mixer, beat egg whites until stiff. Add creamed bananas to egg whites and beat into a creamy, fluffy batter. Add yolks, vanilla, and nut butter and mix well to combine. Stir in Rorie’s Grain Free Flour Blend and baking soda and mix until uniform in texture.
4. Divide batter among prepared muffin cups. Sprinkle with toppings of choice, if desired. Bake for 22–25 minutes, depending on muffin size.
While this recipe can be made with sunflower butter or peanut butter, sunflower butter turns the muffins green (!), and peanut butter gives it a very strong peanut butter flavor — you really have to love peanut butter to use it. Using cashew butter as opposed to almond butter adds sweetness and produces a lighter-colored muffin.