With erythritol icing: Prot: 31g, Carbs: 54g (2g fiber, 6g sugar, 45g erythritol), Fat: 5g, Cal: 211
With cashew cream topping: Prot: 33g, Carbs: 30g (2g fiber, 9g sugar, 15g erythritol), Fat: 11g, Cal: 299


I’m so excited to bring you this layered Protein Birthday Cake recipe. I made it the night before my recent birthday (not knowing if it would turn out) and I totally love it!

All natural protein cake with sprinkles

I’ve been wanting to try a naked cake for a while. Ya know, the kind where the sides are barely covered with any frosting. And I love the look of drip icing, so yeah, this cake!

For the cake layers I used our Vanilla Bean Protein Cake Mix. **Update, we discontinued the mix, but this protein cake mix would be excellent here!

proteinfull baking protein cake mix classic yellow

Protein Birthday Cake - all natural, gluten free, high protein - Andréa's Protein Cakery

For the frosting between the layers, I used a simple recipe with casein protein powder. It came more like a cannoli filling than buttercream, though. Next time I would try a whey/casein blend, maybe even add some Greek yogurt to smooth it out. But this frosting recipe wouldn’t work just with whey protein. Whey + liquid gives a runny icing (or a sticky mess, depending on the whey). The casein gives it the thickness and body it needs to support layers of cake.

proteinfull baking protein cake mix classic yellow

For the drip icing, I used confectioners erythritol mixed with water and purple all-natural food coloring. But I noticed when I computed the macros that the cake is high in erythritol carbs, and that may not work for everyone. Another good option would be to use our Cashew Whipped Cream recipe with either cocoa powder or natural coloring. As long as you can control how runny the icing is, any icing recipe would work!

I watched this tutorial on dripping the icing. My icing came thicker, so my drips are bigger. I used this icing spatula.


My favorite part of this Protein Birthday Cake recipe is the all-natural sprinkles! The last time I made a Confetti Protein Cake, I used freeze dried fruit instead of sprinkles. This time I’ve eased up a bit and went for the sprinkles. One thing to note about the natural ones, though, is that the reds get lost in baking. Only the yellows and blues show up after the cake is baked. I suggest putting them in the casein frosting then, instead of baking them into the cake. You’ll still get the confetti look, and the colors will stay beautiful!


proteinfull baking protein cake mix classic yellow

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Protein Birthday Cake
Nutrition Information
  • Serving size: ⅛ cake
  • Calories: 211
  • Fat: 5g
  • Carbohydrates: 54g
  • Sugar: 6g
  • Fiber: 2g
  • Protein: 31g
Makes one 4-layer 6" cake.
  • 1 package Vanilla Bean Protein Cake Mix --> use Proteinfull Baking protein cake mix
  • 12 large egg whites (396g)
  • ½ cup natural applesauce (111g)
  • 2 tablespoons coconut oil, melted (28g)

Frosting (between layers):

Icing (on top):
  1. Bake cake as instructed on package, as two 6" round cakes.
  2. Once cakes are cool, cut them both lengthwise so you have four layers of cake. We are going to stack them upside down, so the top layer will be straight, without any rise.
  3. Mix casein frosting ingredients (except for sprinkles). Once frosting is mixed well, stir in sprinkles.
  4. Place a little frosting on the cake plate to keep the cake in place.
  5. Place first cake layer. Top with a layer of frosting. Repeat three more times (finish with frosting at the very top).
  6. Add more frosting around the sides to fill in any gaps. Use a bench scraper to smooth the sides.
  7. Set the cake in the refrigerator for about 30 minutes.
  8. Meanwhile, mix your choice of icing.
  9. When the cake is ready, make the drip icing using an icing spatula as in this video.
  10. Top with sprinkles, and enjoy!
With erythritol icing: Prot: 31g, Carbs: 54g (2g fiber, 6g sugar, 45g erythritol), Fat: 5g, Cal: 211
With cashew cream topping: Prot: 33g, Carbs: 30g (2g fiber, 9g sugar, 15g erythritol), Fat: 11g, Cal: 299
The macros here include erythritol carbs, which makes the carb count seem high. Erythritol is a natural, no-calorie sweetener.

Protein Birthday Cake with All-Natural Sprinkles - gluten-free, high-protein, low sugar, diet birthday cake