This Rainbow Cake with White Chocolate is such a fun bake for any occasion. If you’re looking for something to serve up for a birthday, Pride parade, or just something to keep the family entertained – this is the bake for you. Top with white chocolate and sprinkles for something super fun!
How to make rainbow cake: To make this cake, you’ll make the batter as normal and then split it into about 6 bowls. It doesn’t need to be perfectly even but close enough! You then add a different colour to each bowl and stir. Then you add the batter, a different colour tablespoon at a time, to the lined tin. Don’t mix or swirl together! The result is a super fun, super colourful cake!
Don’t be worried if the baked cake doesn’t look very vibrant, the inside keeps the colour much better! Just wait until you slice and you are in for a real treat! This stores pretty well in an airtight container for 2-3 days. Simply slice up however best suits you!
Tips for the best Rainbow Cake with White Chocolate
- Butter: Melted butter works best. Essentially the method is really similar to blondies rather than a classic sponge. This is to prevent the cake from drying with the addition of food colour and the extract stirring it gets.
- Colours: High quality gel food colour gives the best result. Liquid colours won’t give the same vibrant result.
- Topping: A good quality white chocolate (one you would happily eat on its own) is the best option. Make sure it has been at room temperature for at least an hour before cutting or it will break (like mine).
- Decorations: Totally optional! I use edible gold glitter and rainbow sprinkles, but you can use anything you have or just whatever suits you!
For this Rainbow Cake with White Chocolate I use a basic 8′ square pan (I like this one), and recommend using an electric or stand mixer to really combine the butter and sugars (with a mixer like this). If you want more traybake recipes try these Mocha & Pecan Blondies or these Lemon Cheesecake Blondies. For videos and baking inspiration, head on over to my Instagram.
Rainbow Cake with White Chocolate
Ingredients
- 185 g Unsalted Butter Melted
- 150 g Light Brown Soft Sugar
- 130 g Granulated Sugar
- 2 Medium Free Range Eggs
- 2 tsp Vanilla Extract
- 215 g Plain Flour
- 1 tsp Baking Powder
- Approx 4-6 different gel food colourings
For the Topping
- 200 g White Chocolate Melted
- Sprinkles Optional
Instructions
- Preheat the oven to 200C/180C Fan/Gas 6. Line an 8 inch square baking tin.
- Combine the melted butter, granulated sugar and light brown sugar in a large mixing bowl or the bowl of a stand mixer. Combine on high speed for 3-5 minutes. Add the eggs and vanilla and combine again.
- Fold in the flour and baking powder until all combined. Depending on how many colours you want, put a few tablespoons of the batter into small bowls/large mugs. Add a few drops food colouring to each and stir. You should end up with between 4-6 bowls of different coloured batter.
- Add the batter to the lined pan one tablespoon at a time, taking from different colours for each scoop. Don't swirl together or do anything to combine. Once all the batter has been added, bake for 30 minutes.
- Let cool on a wire rack before making the topping. Melt the white chocolate in the microwave in 20 second intervals, making sure it doesn't burn. Then pour over the cake. Add any sprinkles/glitter. Let set before slicing!
