A vanilla chocolate protein cake is a marbled cake made from vanilla and chocolate batter, with two scoops of protein powder mixed in. It takes about 55 to 60 minutes to bake at 165°C. Below is the full recipe, plus answers to the most frequently asked questions: how to make a vegan version, how to store and freeze the cake, how much protein is in a slice, and why a cake sometimes collapses.
What is a vanilla and chocolate protein cake?
It’s a classic butter cake in two colours: you split the batter, mix cocoa powder into one half, and spoon both types of batter alternately into the tin. This creates the marbled effect. The protein powder is simply mixed into the basic batter.
The basic recipe is deliberately simple, making it a great starting point for experimenting. The protein powder does two things: it adds protein to the cake and makes the texture slightly firmer, as the powder absorbs moisture and is less elastic than flour. If you’d like to know exactly what protein powder is and what its benefits are, read about the benefits of protein powder.
What do you need?
For one cake in a standard cake tin, you’ll need the ingredients listed below. Makes about 10 to 12 slices.
- 200 grams of flour
- 1 teaspoon baking powder
- 1 pinch of salt
- 200 grams of butter, at room temperature
- 200 grams of sugar
- 1 sachet of vanilla sugar
- 4 eggs (or 2 ripe bananas, mashed)
- 2 tablespoons of milk or plant-based drink
- 2 tablespoons cocoa powder
- 2 scoops of Ekopura protein powder: natural whey or a vanilla-flavoured vegan protein powder
If you’re using a vanilla-flavoured protein powder, feel free to keep the vanilla sugar in; this will give the flavour a slightly richer depth. If you choose natural whey, the vanilla sugar will remain the main flavouring.
How do you make the vanilla chocolate protein cake?
First, make one basic batter, set aside a third of it for the chocolate layer, and spoon both layers alternately into the tin. Here’s how to do it, step by step:
- Preheat the oven to 165°C. Grease the cake tin with butter and dust it with a little flour.
- In a bowl, mix together the flour, baking powder and salt, then set aside.
- In a second bowl, beat the softened butter with the sugar and vanilla sugar until light and fluffy.
- Add the eggs one at a time and mix the batter until smooth. If using bananas, mash them first and fold them in, in two batches.
- Gradually add the flour mixture and mix until everything is just incorporated.
- Finally, add the milk and protein powder and mix briefly until you have a light, fluffy batter.
- Spoon a third of the batter into a separate bowl and mix in the 2 tablespoons of cocoa powder.
- Spoon the vanilla batter and the chocolate batter alternately into the tin, finishing with a layer of vanilla batter.
- Bake the cake for 55 to 60 minutes. Insert a skewer into the centre: if it comes out clean, the cake is ready.
- Leave the cake in the tin for 5 minutes, then turn it out onto a wire rack and leave it to cool completely before cutting.
How do you achieve a nice marbled effect?
Spoon the two types of batter into the tin in layers and run a knife or skewer through it once in an S-shape. More stirring means less marbling.
The reason is simple: the pattern is created because the two types of batter remain side by side rather than mixing together. Every extra stir blends them further, until you’re left with a single, uniform, light-brown cake. So use generous spoonfuls rather than thin streams, and stick to that single movement through the batter.
Tips and variations
- Don’t mix the batter for longer than necessary once the flour has been added. Flour forms gluten when stirred, and too much gluten makes the cake chewy rather than light and fluffy.
- Don’t replace the fat with fat-free alternatives such as apple sauce. Fat helps retain moisture in the crumb and prevents the cake from becoming dry, especially when protein powder is added.
- Add a handful of chopped dark chocolate or walnuts to the chocolate mixture for extra texture.
- A teaspoon of espresso powder in the chocolate batter enhances the cocoa flavour.
- If you’d like the cake to be a little less sweet, reduce the sugar to 150 grams. Below that amount, the texture will also change, as sugar retains moisture and keeps the crumb soft.
When should you enjoy a slice?
This cake goes well with coffee, for breakfast with a bit of quark or yoghurt on the side, or as a snack around a training session. Because you cut it into slices, you’ve got a handy portion straight away.
A slice is easy to pack in your bag or lunchbox. If you want to know how much protein you need each day, our how much protein do you need per day guide can help you work it out.
Variations
These combinations work just as well with a scoop of protein powder mixed into the basic batter:
- All-chocolate Omit the vanilla layer and mix the two tablespoons of cocoa into the whole batter for a cake that’s all chocolate.
- Chocolate with banana Replace the eggs with two mashed ripe bananas; the crumb will then be slightly moister and naturally sweeter.
- Chocolate with oatmeal Replace half the flour with finely ground oatmeal for a firmer, denser crumb.
- Raspberries Fold a handful of fresh or frozen raspberries into the vanilla batter just before pouring it into the tin.
- Blueberries Lightly toss the berries in a little flour first; this will help them stay evenly distributed rather than sinking to the bottom.
- Raspberries and blueberries Combine both soft fruits; a vanilla-flavoured vegan protein powder goes well with this.
- Coconut and chocolate Replace two tablespoons of flour with grated coconut and finish the cooled cake with some desiccated coconut.
Frequently asked questions
Can you make a vegan version?
Yes. Replace the whey with a vegan protein powder, the butter with vegan butter or coconut oil, the milk with a plant-based drink, and the eggs with the 2 mashed bananas from the recipe. The cake will then be slightly denser and moister than when made with eggs, as eggs set during baking and thus trap air; bananas do not. If necessary, add an extra half teaspoon of baking powder to compensate for this.
How do you store the cake, and can you freeze it?
Store the cake in an airtight container. It will keep for about three days at room temperature, and slightly longer in the fridge, although it will become a bit firmer there. It freezes very well: first cut the cake into slices, place baking paper between them and freeze them. You can defrost a slice at room temperature in about an hour, or warm it briefly in the oven at 150°C.
How much protein is there in a slice?
That depends on how thick you cut the slices and which protein powder you use. The protein in this cake comes from the eggs, the flour and the two scoops of protein powder. If you cut the cake into 10 to 12 slices, you’ll get roughly 6 to 9 grams of protein per slice, slightly less in the vegan version. For the exact amount per scoop, check the packaging of your own protein powder, as this varies by type and flavour.
Why does my cake sink in the middle?
This is usually because the cake was taken out of the oven too early or because the oven door was opened whilst it was baking. A cake rises due to air and gases from the baking powder, and these air bubbles only stay in place once the protein from the eggs and the starch from the flour have set. If the door is opened before this structure is ready, the batter cools down and the bubbles collapse again. So keep the oven door closed for the first 45 minutes, then check with a skewer and let the cake rest in the tin before turning it out.
Give it a go yourself
For this recipe, we used Ekopura Purely Natural, our organic natural whey protein powder with no unnecessary additives. If you’d prefer a vegan option or a vanilla-flavoured powder, you’ll find them in the protein powder collection. More recipes to try out can be found on the recipes page.
