Vegan Watermelon Cake

Friday 6 July 2018

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I just can't get enough watermelon!

Growing up, watermelon would be eaten at any given time. Being from a Turkish family, everybody would see themselves as watermelon connoisseur and can tell you where to find, and how to choose the best and juiciest watermelon without even cutting it open. 90% of the time, they were usually right. Another Turkish tradition is to eat your watermelon with a slice of hellim (halloumi), which sounds strange, but the taste from the super sweet fruit combined with the salty cheese made for the perfect summertime snack. I was always a huge hellim fan, so my watermelon to cheese ratio was never quite right.

My tradition now is to eat a few slices each and every morning. It may give me more trips to the bathroom, but I just can't resist it. Once the watermelon comes out, I know summer is here.

While planning my content schedule recently, I was thinking to myself, "what kind of summer inspired bake should I do?" Amongst my long list (more is still to come), watermelon cupcakes were placed right at the top. Now you might be thinking these don't look like cupcakes, and you are of course right. Baking is one of my favourite style of post to create, and I try and get at least one scheduled in a month, but I have never made a cake recipe. Numerous amounts of cupcakes, but never a cake.

vegan watermelon cake

Challenge accepted!!

Baking a cake is very different from baking cupcakes. Yes the recipe is the same, but you've got more to think about; layering up your tiers, making sure they're all equal and even, how you're going to coat and decorate the cake. A little more precision than your average piped buttercream.

So, let's start talking about the flavours of this cake. You've got a 3 tiered cake, with a red, chocolate chip sponge, sandwiched between a layer of watermelon chia jam and vanilla buttercream, which also coats the entire cake and decorated with more chocolate chips. The chocolate chips inside the sponge not only represents the seeds, but it gives the cake a new chocolatey texture.

.@helloaycan is sharing her vegan watermelon cake recipe here!

And yes, you did read that right, there is watermelon chia jam sandwiched in the cake. At the last minute, I had the idea to incorporate the flavours of the watermelon, which is a lot harder than most fruits seeing as it is mostly made up of water. As I was so in love with my chia jam cupcakes, I thought I'd give this a go and see what would come out. I would like to report that it has worked out very well. It's not as sweet as your standard fresh watermelon, it's much sourer, but it helps to balance out all the sweetness. I piped a layer of white buttercream, smoothed it out and then spooned over the chia jam between each layer.

There is a lot of firsts in this recipe, baking a cake, but also crumb coating. Crumb coating is where you take your buttercream and coat your cake. This keeps the crumbs in and stops them from mixing up with your final layer of buttercream. It's not always necessary, but with the delicate and soft sponge of this recipe, I'd definitely recommend. It also adds to the realisticness of a watermelon with the white rind. It doesn't have to be neat at all as it's going to get hidden.

Now, having to buttercream the entire cake was my biggest stress. I don't have a turntable, or a cake scraper so I assumed everything was going to go wrong, but sometimes all you need to do is use your initiative and work with what you've got lying around your kitchen. I very slowly turned the board around that my cake was placed on, and using the edge of a spatula and keeping my hand very still, smoothed the buttercream around. Doesn't look too bad, does it? I have started a very long list of baking tools I need.

Overall, for my first cake on my blog, I do think it could have gone a lot worse. The taste is absolutely delicious, which is all that matters. Now, let's get to making this fruity wonder.

vegan watermelon cake


This recipe makes 14 healthy servings of cake.


  • 2 cups chopped and deseeded watermelon
  • 2 tbsp freshly squeezed lemon juice
  • 1-2 tbsp agave syrup (add more if you prefer it sweeter)
  • 2 tbsp chia seeds
  • CAKE
  • 2 cups/455ml dairy-free milk
  • 2 tbsp + 2 tsp/40ml apple cider vinegar
  • 3 cups/443g self-rasing flour
  • 2 cups/350g caster sugar
  • 1/2 tsp bicarbonate of soda
  • 1/2 tsp baking powder
  • 1/2 cup/115ml flavourless oil
  • 2 tbsp vanilla extract
  • 1 cup/150g + a lil extra for decorating dairy-free chocolate chips
  • red food gel
  • 1/2 cup/100g dairy-free butter
  • 1 1/2 cup/250g vegetable shortening
  • 6 cups/800g icing sugar
  • 2 tsp vanilla extract
  • red + green food gel


  1. Blend a quarter of the watermelon and leave to one side. In a saucepan on a low heat, add in the chopped watermelon, lemon juice and agave syrup. Keep stirring so it doesn't stick to the bottom. Using the back of a fork, crush the watermelon.
  2. Once thickened and most of the watermelon has dissolved, pour in the blended watermelon and chia seeds and stir for a few more minutes. Pour into a glass lidded jar and store in a fridge for at least an hour.
  3. Pre-heat the oven to 180 degrees C / 160 degrees C (fan) / 350F / gas mark 4. Line 3 8" cake tins.
  4. In a small bowl, stir the dairy-free milk and cider vinegar, and leave for 10 minutes to curdle. In a large bowl, sift the flour, caster sugar, bicarbonate of soda, and baking powder, and mix together with a spoon.
  5. Pour the dairy-free milk and cider vinegar mix into the dry ingredients, and add the flavourless oil, and vanilla extract. Add in the red food gel to desired colour. Stir in the chocolate chips.
  6. Evenly pour the mixture into the lined tins, and straight into the preheated oven for 15-20 minutes. They should leave a knife clean when tested, but also feel springy to touch. Leave them to cool on a cooling rack.
  7. To prepare the buttercream, leave the butter and vegetable shortening at room temperature for 15 minutes. In a large bowl, beat together using a hand or standing whisk, the vegetable shortening and butter until it's light and creamy. Add the vanilla extract. Gradually pour in the sifted icing sugar, half a cup at a time. If it starts to get dry, add a little dairy-free milk, one tsp at a time.
  8. Once the cakes have cooled, place one layer onto a board and pipe on your buttercream, and spread over your chia jam. Repeat with the remaining layers. Using a thin layer of buttercream, crumb coat your cake, and leave it in the fridge for at least 2 hours.
  9. Split the remaining buttercream into two bowls, one with a larger amount of buttercream. Mix in the green gel in the larger amount, and red in the smaller amount. Once the icing has hardened, pipe the icing around the cake and smooth it over with a cake scraper or spatula. Sprinkle remaining chocolate chips on top of the cake.
vegan watermelon cake

I am currently eating my way through a healthy slice of cake for "research purposes". How am I suppose to talk about a cake I cannot taste? Let me know in the comments below if you're a watermelon fan or not, and any cake tips you can offer... I really need them!