Marble cake is a classic childhood treat and is always a hit with the whole family. Chocolate and vanilla batters get swirled together before baking to create a beautiful pattern and the finished cake is topped with a rich, creamy mocha frosting. You’ll love every bite of this delicious cake!
I have very clear memories of my childhood baking featuring marble cake. It was something that was so much fun to make as a kid as you would swirl the often brightly coloured batters together to make artistic patterns, only to be realised once cutting into the finished cake.
This cake is based on that inspiration but here we are sticking with the classic flavour combo of vanilla and chocolate. However if you want to give the rainbow option a go, just add some food colouring to the vanilla batter, experiment and have fun.
But back to today’s cake. This marble sheet cake is so simple to make, starting with just a single batter! We are also making it in a large rectangular pan instead of your usual round one. I just love making cakes like this as it makes slicing and serving so much easier.
The cake is made with a classic vanilla butter cake batter, which has some cocoa powder added to half and suddenly the decision between whether to have chocolate or vanilla cake has been sorted!
I have recently rediscovered a love of the simple butter cake, mostly because it’s so quick and easy to make and creates such a tender, delicate texture. As part of my journey into reliving the classic cakes I grew up with, I just knew that I needed to make a marble cake because they are so much fun and taste amazing.
It’s always a family favourite thanks to that delicate swirl providing a little bit of vanilla and chocolate flavour in every bite. The key is that the cake must taste like BOTH flavours, so make sure not to overmix them when creating your swirl – once through gently with a knife is enough.
This cake is so buttery and soft, and don’t even get me started on the mocha frosting. It’s the same frosting that I used on my mini vegan chocolate cake and I love how rich and fudgy it is despite not containing real chocolate. It’s the perfect go to chocolate frosting.
For this recipe you’ll need your usual suspects of butter, eggs, sugar and milk. As I’m dairy-free, I am using a dairy-free spread in place of butter and my favourite vanilla almond milk.
I’m also using caster sugar instead of regular white sugar to make sure the texture of my finished cake is super smooth and ensure the best result, but you can substitute regular white sugar here without too much difference if you need to.
For this cake, I’m just using cocoa powder for the chocolate cake and the frosting as I want a cake that tastes delicious but is still super simple to make and can be thrown together with just key pantry staples. But let me tell you that this is no compromise on flavour.
How to make marble cake
To make this cake, you’re going to need a couple of medium to large mixing bowls and an electric mixer. You can use either a handheld mixer or a stand mixer, the preference is yours.
For me, I love using my handheld for the cake batter as I feel it gives me more control, while I will never make frosting again without using my stand mixer as it makes the process so quick and easy.
For the cake, we are going to start by making our vanilla butter cake batter. This process begins with the classic technique of creaming together the sugar and butter so place them both in your bowl and use your electric mixer to beat them together until pale and creamy.
From here, add in your vanilla followed by 1 egg at a time, making sure to beat through each addition before adding in the next. This process is what is going to make our cake light and delicate.
Once that’s complete, sift together your dry ingredients into a separate bowl and give them a whisk to combine. Slowly add in some of the dry ingredients to the batter along with some of the dairy-free milk. Mix to combine.
Repeat this process, alternating the dry ingredients and the milk until everything has been incorporated. Be very careful only to mix enough to just combine, as we don’t want to overmix the batter.
Pour half of the batter into a separate bowl and add in your cocoa powder. Gently mix it through until combined, again making sure not to overmix. This batter will be thicker than the vanilla.
Grease and line your rectangular cake pan, I use one that is 30cm x 20cm, and drop alternate scoops of each batter into the bottom of the pan. Smooth out the top of the batter with a spatula or knife, before using a flat knife that’s touching the bottom of the pan to gently move through the batter in a swirl pattern.
Again, make sure to not over do this step so that they cake flavours do not get too mixed together, but rather just gently mixed together.
Place the cake in a preheated oven to bake for 30 minutes or until the top is lightly golden and a skewer inserted comes out clean.
Let the cake cool in the pan for about 10 minutes before gently lifting it out to cool completely on a wire rack.
Make the mocha frosting by placing all the ingredients into a bowl and beating together until smooth and silky. Spread the frosting over the top of the cooled cake and then slice into squares to serve.
If you really don’t want to add the coffee to the frosting you can use a little dairy-free milk instead, but I promise the coffee in the frosting is incredible and makes it super rich.
How to store this marble cake
You can make the cake ahead of time and wrap it in plastic wrap and aluminum foil and store in the freezer for up to 3 months. Let it defrost in the fridge or on the kitchen counter overnight still wrapped up. Then to serve simply make the frosting and it will taste freshly baked.
To store frosted cake, keep it in an airtight container in a cool spot or in the fridge for about 3 days. You can also freeze the frosted cake for up to one to two months. Place it on a plate and cover in plastic wrap to freeze on a single layer. Again defrost overnight in the fridge or let come to room temperature on the bench.
More classic cake recipes:
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Marble Sheet Cake
- ⅔ cup (160 grams) dairy-free butter
- ¾ cup caster sugar
- 1 teaspoon vanilla
- 3 eggs room temperature
- 2 cups plain flour
- 2 teaspoons baking powder
- ¼ teaspoon salt
- ½ cup dairy-free milk
- 2 tablespoons cocoa powder
For the Mocha Frosting
- ¼ cup (60 grams) dairy-free butter
- ½ cup cocoa powder
- 1 ½ cups icing sugar
- 1-2 tablespoons strongly brewed coffee cooled
- Preheat the oven to 180°C and grease and line a 30cm x 20cm rectangular baking pan with cooking spray and baking paper.
- In a large bowl, cream together the dairy-free butter and caster sugar with an electric mixer until the mixture is light and fluffy and starting to get pale in colour. Add in the vanilla and continue to beat. Gradually add the eggs one at a time, beating the mixture completely after each addition.
- In a separate bowl, sift together the flour, baking powder and salt and mix to combine. Slowly add the flour mixture a little at a time, to the wet ingredients, alternating with the dairy-free milk mixing until just combined, being careful not to over mix.
- Spoon half of the mixture into another bowl and add in the cocoa powder. Mix until just combined.
- Spoon the batter into the lined cake pan, alternating between the chocolate and the vanilla. Smooth down the top and gently drag a knife through the batter, lightly touching the bottom, to create gentle swirls. Place the pan in the oven and bake for 30-35 minutes or until the cake is cooked through and springs back when lightly touched. Let the cake cool in the pan for 10-15 minutes before turning out onto a wire rack to cool completely.
- Make the frosting by placing all of the ingredients into a bowl of a stand mixer with the paddle attachment fitter, or use a hand held electric beater to beat everything together until smooth and creamy. If the frosting is too thin, add a little more icing sugar, and if it’s too stiff, add a little more coffee.
- Using a flat knife, spread the frosting over the cooled cake. Cut into squares to serve.