This Chocolate Traybake Cake is a chocolate sheet cake that's so easy to make, with such a delicious chocolatey result! Traybake cakes are brilliant for parties and serving a crowd as they are so quick to slice up. They're also super versatile as you can decorate them any way you like! This indulgent cake has a moist chocolate sponge that's studded with chocolate chips, and it's slathered with a rich chocolate buttercream that has real chocolate mixed into it for extra luxury!
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Ingredient Tips & Equipment Information
- Make sure all your ingredients (particularly the butter and eggs) are at room temperature before you start baking.
- I used a baking spread for the cake and unsalted butter for the buttercream.
- If you can't get hold of light brown soft sugar, you can also use regular caster sugar for this cake.
- You will need a 12" x 9" traybake tin for this recipe. However, if you want to make it in a 9" square tin, check the recipe notes for the measurement details.
- You can decorate this cake with anything you like! If it is for someone's birthday, perhaps their favourite chocolates on top. Fresh strawberries or raspberries would also look fabulous!
- You can use any cocoa powder for this cake, of course the better quality it is, the better flavour it will have. Also do make sure you are using cocoa powder and not a hot chocolate powder.
- The chocolate chips are optional, but I recommend them!
- Although I provide cup measurements, I highly recommend weighing your ingredients out using digital kitchen scales. It is the most accurate way to measure ingredients and will ensure the best results. Digital scales are very low cost and can be purchased for around £12 ($16.50) .
- For teaspoon (tsp) and tablespoon (tbsp) measurements, please use measuring spoons and not the type of spoons you eat with. Again this will ensure accuracy and provide the best results.
For the full recipe with measurements, head to the recipe card at the end of this post.
How to make Chocolate Traybake Cake
To make the cake, mix together the baking spread and light brown soft sugar, for 2-3 minutes until fluffy. Then whisk in eggs and vanilla extract.
Add the milk, self raising flour, cocoa powder, bicarbonate of soda and baking powder, and gently whisk or fold in. Finally, mix in the chocolate chips and spread the mixture out into the tin.
Bake the cake for 25-30 minutes or until a thin skewer inserted in the centre comes out clean. Leave to cool fully. For the buttercream, mix softened butter, icing sugar, cocoa powder and double cream together. Then add melted dark chocolate and mix until smooth.
For the full recipe with measurements, head to the recipe card at the end of this post.
How long does the cake last for and can you freeze it?
The cake will last for 3-4 days in an airtight container in a cool place. You can freeze both the cake and the buttercream. To freeze them separately, wrap the cake well in cling film or put it in an airtight container. The buttercream can be frozen in a sealed tub. To freeze the cake decorated, freeze on a plate until frozen solid, then carefully wrap in cling film. Remove the clingfilm when you take the cake out of the freezer to defrost, as if it defrosts with it still on it could damage the appearance of the buttercream.
Can you make this cake with plain/all purpose flour?
Self raising flour, which is very commonly used in the UK where I am based, already contains a raising agent and a little salt too. Therefore if you want to swap it for plain or all purpose flour, you will need to add some additional baking powder and also a little salt if you like. Some people like to add salt to cake recipes and some don't, so I'll leave that up to you as it won't affect the bake. The general advice is to add 2 teaspoons baking powder (a measuring teaspoon, not the kind you stir your coffee with) per every 200g plain or all purpose flour. So for this recipe you'd need to add an additional 1 ¾ teaspoons baking powder. Please note, I have not tested this recipe using plain or all purpose flour.
What size tin do you need for this cake?
This recipe is best made in a 12" x 9" (36.5cm x 26cm) traybake tin with deep sides (4cm or 1.5"). However, if you'd prefer to make it in a smaller 9" square tin, check the recipe card notes section for details on how to change the measurements and baking time.
How many people does this cake serve?
It completely depends how you slice it up, which is great because it makes this such a versatile cake for parties and gatherings. I love a big chunk of cake so I cut it into 12 slices, but for a party you may prefer to cut it into smaller slices so it feeds more people. You can cut into 16 slices, or even 24 slices.
Can this cake be made gluten free?
Yes! For gluten free you can replace the self raising flour with a gluten free self raising flour blend. If you only have a gluten free plain flour blend, you will need to add additional baking powder. The general advice is to add 2 tsp baking powder per 200g flour, so for this recipe you'd need to add 1 ¾ additional teaspoons baking powder. You may also like to add ½ tsp Xanthan Gum for better texture. Please do check the labels for everything you use to make the cake if you are serving it to someone with an allergy or intolerance.
Can this cake be made dairy free?
For a dairy free version, use a dairy free baking spread and dairy free milk for the cake. For the buttercream you will need a dairy free butter alternative. I recommend Flora Plant or the Stork Baking Block for the buttercream, as they give the best texture. You will also need to use a dairy free alternative to cream for the buttercream, and make sure the dark chocolate you use is dairy free. Please do check the labels for everything you use to make the cake if you are serving it to someone with an allergy or intolerance.
Do you need an electric mixer to make this recipe?
While you can absolutely make this recipe with a wooden spoon and some elbow grease, I do recommend using an electric mixer for the best results. The cake will be lighter and fluffier when made with an electric mixer. The buttercream will also be smoother. You don't have to use an expensive stand mixer either, you can get electric hand whisks for as little as £10!
Can this cake be made into a larger cake?
Yes, to make this recipe into a larger cake you might like my Chocolate Birthday Cake.
More tips for making the Chocolate Traybake Cake:
- I spread the buttercream onto the cake, but you could pipe it on if you prefer.
- I used dark chocolate chips for the cake, you can omit them or use white or milk chocolate chips instead.
- You can decorate this cake with anything you like - chocolate sprinkles, grated chocolate, your favourite sweets or chocolates, fresh fruit etc.
Troubleshooting
If you have any questions about this recipe, or if something went wrong and you need help, please use the comment form below and I will get back to you. You can also get in touch with me on my Twitter, Instagram or Facebook. I'd love to hear from you!
Recommended equipment & ingredients
- Traybake tin
- Mixing bowls
- Measuring spoons
- Cooling rack
- Kitchen scales
- Electric hand mixer
- Piping bags
- Dark chocolate
- Angled palette knife
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More chocolate recipes...
Chocolate Traybake Cake
Ingredients
For the cake
- 225 g Butter or baking spread unsalted, softened
- 225 g Light brown soft sugar
- 4 Eggs large
- 1 tsp Vanilla extract
- 75 ml Milk
- 175 g Self raising flour
- 50 g Cocoa powder
- ¼ tsp Baking powder
- ¼ tsp Bicarbonate of soda
- 100 g Chocolate chips optional
For the buttercream
- 200 g Butter unsalted, softened
- 350 g Icing sugar
- 50 g Cocoa powder
- 65 ml Double cream
- 100 g Dark chocolate melted
Instructions
- Pre-heat your oven to 160C Fan/180C/350F/Gas Mark 4, and grease and line a 12" x 9" traybake tin
- Make the sponge by mixing the baking spread (or butter) and light brown soft sugar in a large bowl until fluffy, about 2-3 minutes, ideally using an electric mixer
- Add the eggs, milk and vanilla extract, and whisk until fully incorporated
- Gently whisk or fold in the self raising flour, cocoa powder, baking powder and bicarbonate of soda
- Gently fold in the chocolate chips
- Pour the mixture into the tin, smooth it out if needed to spread it out evenly
- Bake for 25-30 minutes or until a skewer inserted in the centre comes out clean. Leave to cool fully either in the tin or on a cooling rack
- To make the buttercream, start by melting the dark chocolate. I melt mine in the microwave, start with a 30 second blast, then stir, then continue with 10 second blasts, stirring between each one until it is fully melted. Set it aside to cool
- Mix the butter in an electric mixer with the paddle attachment for a few minutes. Add the icing sugar, cocoa powder and double cream and mix until well combined
- Add the cooled dark chocolate and mix in until combined
- Spread or pipe the buttercream all over the cake
- To serve, decorate as you prefer, then slice into squares. Store any leftovers in an airtight container in a cool place and eat within 3 days
Video
Notes
- Make sure all your ingredients (particularly the butter and eggs) are at room temperature before you start baking.
- I used a baking spread for the cake and unsalted butter for the buttercream.
- If you can't get hold of light brown soft sugar, you can also use regular caster sugar for this cake.
- You will need a 12" x 9" traybake tin for this recipe. However, if you want to make it in a 9" square tin, check the recipe notes for the measurement details.
- You can decorate this cake with anything you like! If it is for someone's birthday, perhaps their favourite chocolates on top. Fresh strawberries or raspberries would also look fabulous!
- You can use any cocoa powder for this cake, of course the better quality it is, the better flavour it will have. Also do make sure you are using cocoa powder and not a hot chocolate powder.
- The chocolate chips are optional, but I recommend them!
- Although I provide cup measurements, I highly recommend weighing your ingredients out using digital kitchen scales. It is the most accurate way to measure ingredients and will ensure the best results. Digital scales are very low cost and can be purchased for around £12 ($16.50) .
- For teaspoon (tsp) and tablespoon (tbsp) measurements, please use measuring spoons and not the type of spoons you eat with. Again this will ensure accuracy and provide the best results.
- 170g Butter or baking spread
- 170g Light brown soft sugar
- 3 Large eggs
- 1 tsp Vanilla extract
- 130g Self raising flour
- 38g Cocoa powder
- Scant ¼ tsp Baking powder
- Scant ¼ tsp Bicarbonate of soda
- 56ml Milk
- 75g Choc chips
Simon
Looks delicious and easy to make!
Maria
I made this cake so easy to make
I will be using this recipe for all my cakes.
Christine Vedhasinghe
Easy to make and it turned out delicious
thebakingexplorer
Thank you so much for the lovely feedback Christine!
Natalie
Can I use milk chocolate instead of dark chocolate? And can I also use a electric hand whisk to make the buttercream?
Aisha
I LOVED this recipe so much. The cake was moist and delicious and the buttercream was super rich, chocolatey and creamy. Thanks for another amazing recipe Kat. Xx
Polly
Easy to make and very easy to eat. It's a really delicious sponge with a divine luscious buttercream. I thoroughly recommend!
thebakingexplorer
Thanks so much Polly!
C Ryan
Lovely,moist and light
Clare
This recipe looks lovely and want to use this for a cake but i have just brought a 13inch by 9inch rectangle tin and i see this is 12 inch by 9. What measurements would i use. Worried if i use these measurements the sponge will be too thin? Can you advise at all. Many thanks x
thebakingexplorer
Hi Clare, 13x9 is not much bigger so the same measurements should be fine and it won't be a thin sponge
Christine
Really easy, moist and tasty chocolate tray bake. I made it gluten free by subbing the regular flour for gluten free self raising and no-one noticed any difference. Can see me making this a lot and I think it will freeze (uniced) well too.
Emma
The best chocolate cake I’ve ever made, I will be using this recipe every time now. I did use plain flour plus 2 tsp extra baking powder and it was perfect, the sponge was so light. Thank you