Blend the egg whites, apples, and vanilla for about 30 seconds.
Add the rest of the ingredients for the cake and blend for another 30 seconds. Scrape down the sides of the blender with a spatula, if necessary, and blend again until well combined (another 30 seconds or so).
Pour batter into a 7" or 8" square pan, or any baking pan of similar size. (If you are not using silicone bakeware, be sure to line your pan with parchment paper.)
Bake for 20-25 minutes.
Remove from oven and let cool.
Mix maple syrup with cloves, and brush over top of cake.
Enjoy!
Notes
Ingredient SubstitutionsSubstitute the whey and rice protein powders with pea protein powder for similar results.Replace chopped apples with unsweetened applesauce if you don't have a blender.Use honey or agave syrup instead of maple syrup for a slightly different glaze flavor.
Recipe Variations
Add chopped nuts or raisins to the batter for texture.
Top the cake with a sprinkle of powdered erythritol or cinnamon for extra decoration.
Use a muffin tin instead of a square pan for individual servings.
Storage InfoRefrigerate the gingerbread protein cake for up to 5 days. Let it come to room temperature before serving.For longer storage, freeze slices wrapped in plastic wrap in a sealed container for up to 3 months. Thaw overnight in the fridge.