Say hello to the BEST Chocolate Traybake – a.k.a Chocolate Sheet Cake! This moist chocolate cake topped with decadent chocolate frosting is perfect for birthdays, celebrations and bake sales. And the best part? It is SO EASY to make!
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CHOCOLATE TRAYBAKE
Tray bakes are currently in vogue – just look at the runaway success of Edd Kimber’s One Tin Bakes (an awesome baking book, highly recommended).
The reason? They are easy peasy, low effort, take mere minutes to prepare AND they can feed a crowd. Perfect for fuss-free birthday parties when you haven’t got the time to create a big layer cake.
This foolproof chocolate tray bake recipe is my go-to cake whenever my kids want to bring something to school to celebrate their birthdays. I can tell you that there’s never a crumb left 🙂
Here’s what you will need
- Plain flour (all purpose flour) plus baking powder and bicarbonate of soda.
- Sugar: ideally half caster and half soft brown sugar
- Cocoa powder: use the best quality unsweetened cocoa powder
- A little espresso powder: this enhances the chocolate flavour but if you prefer not to use any you can simply leave it out
- Three medium eggs
- Softened butter or margarine (I used Stork in the recipe video)
- Buttermilk or milk plus a little lemon juice
Chocolate frosting
- Softened butter
- Icing sugar
- Cocoa powder
- Milk, heated in the microwave for 30 seconds until a little warm
- Melted chocolate: use good quality dark chocolate
Useful Tools & Equipment
- Digital scales – I use a scale for all my bakes
- Measuring spoons
- A rectangular cake tin
- Cake lifter – for transferring cakes safely
MAKE THE CHOCOLATE SPONGE CAKE
Make sure your ingredients are at room temperature. Put the flour, sugar, cocoa powder, baking powder, bicarbonate of soda and espresso powder in a mixing bowl (or the bowl of your stand mixer). Use a balloon whisk or fork to stir so they are combined.
Add the softened butter, eggs, buttermilk and mix together on low speed initially, increasing to maximum speed until batter is smooth. Make sure to use a spatula to scrape the bottom and sides of the bowl to ensure no sneaky dry pockets of flour lurk underneath!
Transfer the batter to a lined rectangular tray (9×13 inches) and bake in a preheated oven for 35-40 minutes. Test the cake is done with a skewer – it should come out clean and crumb free. The cake should be risen and just coming away from the edges of the tin.
Cool the cake in the tin for 10 minutes then use the overhanging paper to carefully lift onto a wire rack to cool completely.
MAKE THE CHOCOLATE FROSTING
Put the chocolate in a bowl and melt in the microwave, in short 30 second bursts, until it melts. Alternatively, set the bowl over a pot of simmering water and allow if to melt gradually using this double boiler method. Leave the chocolate to cool slightly.
Put the icing sugar and cocoa powder in a mixing bowl (or the bowl of your stand mixer) and mix together to combine. If you can, sift the ingredients into the bowl. I must admit I am usually too lazy to do that!
Add the softened butter and start mixing on low speed, gradually adding the milk until frosting is well combined. Add the melted and cooled chocolate and beat together until the frosting holds soft peaks. Go ahead and taste it… try not to eat it all!
ASSEMBLE THE CHOCOLATE TRAYBAKE
Use a palette knife to spread the frosting over the cake, swirling the surface. This cake has A LOT of frosting (if you haven’t eaten it beforehand).
Add sprinkles, chocolate buttons, smarties or leave plain. When you are ready to serve, slice the cake using a serrated knife, wiping the knife clean between each slice.
This chocolate sprinkle cake will keep for 2-3 days at room temperature but it is best eaten when fresh.
My Most Popular Cake Recipes
Chocolate Traybake
Equipment & Tools
Ingredients
- 300 g (2 ½ cups) flour plain / all purpose
- 60 g (½ cup) unsweetened cocoa powder
- 330 g (1 ⅔ cups) sugar use half granulated, half light brown if you like
- 1 tbsp espresso powder (optional)
- 1 tbsp baking powder
- ½ tbsp bicarbonate of soda
- ½ tsp salt
- 200 g (7/8 cup) unsalted butter or Stork softened
- 3 medium eggs
- 180 ml (3/4 cup) whole milk
- 2 tbsp lemon juice to sour milk (or use buttermilk)
Chocolate Frosting
- 260 g ( 2 cups) icing sugar
- 6 tbsp unsweetened cocoa powder
- 150 g (⅔ cup) softened unsalted butter
- 120 ml (½ cup) milk slightly warm
- 175 g (1 cup) dark chocolate chips melted and cooled
To decorate
- chocolate sprinkles, M&Ms, chocolate shavings
Instructions
- Preheat the oven to 170C (340F). Line a 9x13inch rectangular with baking paper.
- Mix the milk and lemon juice and leave to stand for 5 minutes.
- Put the flour, cocoa powder and sugar in large bowl. Add the baking powder, bicarbonate of soda and salt and mix together using a balloon whisk.
- Add the butter, eggs and soured milk.
- Start beating on the lowest speed setting until the ingredients start to come together.
- Increase the speed gradually, until the batter is completely smooth. Stop the mixer and scrape the sides and bottom of the bowl to make sure everything is incorporated.
- Transfer the batter in the prepared tin and level.
- Transfer the batter into the prepared cake tin and bake for 35 -40 minutes.
- Check the cake is done by inserting a skewer in the centre – it should come out clean, the cake should be well risen golden and springy to the touch. Cool the cake before frosting.
Chocolate Frosting
- Put the chocolate in a bowl and melt in the microwave, in short 30 second bursts, until it melts. Alternatively, set the bowl over a pot of simmering water and allow if to melt gradually using this double boiler method. Leave the chocolate to cool slightly.
- Put the icing sugar and cocoa powder in a mixing bowl (or the bowl of your stand mixer) and mix together to combine. If you can, sift the ingredients into the bowl.
- Add the softened butter and start mixing on low speed, gradually adding the milk until the frosting is well combined.
- Add the melted and cooled chocolate and beat together until the frosting holds soft peaks. Go ahead and taste it… try not to eat it all!
Assemble the Cake
- Use a palette knife to spread the frosting over the cake, swirling the surface. This cake has A LOT of frosting (if you haven’t eaten it beforehand).
- Add sprinkles, chocolate buttons, smarties or leave plain. Slice the cake using a serrated knife, wiping the knife clean between each slice.
Video
Notes
Nutritional Info
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Claudia says
Very easy, made with a toddler and still successful!
Jill says
Made this delicious tray bake last week for my granddaughter’s birthday, we all loved it, the all in one method is easy to follow and turned out great, easily cut into a good 2 shape ,
Making it again today .
Ant says
This looks lovely. What do you mean by espresso powder though please? Is that instant espresso coffee?
Lucy Parissi says
Hi – yes that’s what I mean (although it is optional) x
Amy says
Should the oven temperature be reduced if using a fan oven, or is 170 deg for fan oven? Thanks
Lucy Parissi says
Yes reduce to 160
Sam Marshall-Love says
Hi Lucy, Sam again 🙂 I want to scale up this cake (as it’s so good) for my son’s birthday party, into a 12×16″ tray and keep the depth. I’ve attempted the calculations and failed miserably 🙂 so would you please be able to advise what % increase I should apply to the current ingredient list to make the larger size, and what increase in baking time I should anticipate please? Many thanks for your awesome recipes!!
Lucy Parissi says
Hi Sam – I have done some calculations here but since I haven’t tested this I am not 100% sure it is right. I would suggest you double the recipe and use as much batter as you need and then bake cupcakes with any leftover.
If you want to try my calculations, see below
450g flour plain / all purpose
90g unsweetened cocoa powder
450 g sugar use half granulated, half light brown if you like
1 1/2 tbsp espresso powder (optional)
1 1/2 tbsp baking powder
½ tbsp bicarbonate of soda
½ tsp salt
300 g unsalted butter or Stork softened
4 large eggs
270 ml whole milk
2 tbsp lemon juice to sour milk
Chocolate Frosting
390 g icing sugar
8 tbsp unsweetened cocoa powder
225g softened unsalted butter
180 ml (½ cup) milk slightly warm
260g dark chocolate chips melted and cooled
Samantha Marshall-Love says
Hi Lucy, thanks so much for your reply. I decided to try a 160% increase on the base recipe and it appears to have worked perfectly, so so pleased! I made a test one last night and cooked it for an extra 5/10 minutes, and it looked so good I have just made another one to layer up 🙂 Thanks again, looking forward to trying out some more of your recipes xx
Sam says
I don’t normally leave comments but I have to say this worked perfectly and my children love it. They don’t like icing so I left the cake plain, it was a great hit, everything worked in the recipe. Will try more from this site as that’s a rare occurrence I find!! Thanks Supergoldenbakes 🙂
Lucy Parissi says
What a wonderful comment you made my day ❤️❤️❤️
Natalie says
May I use milk chocolate chips instead of dark for the frosting? I would like to make this for my little sisters birthday and she’s not really a big fan of dark chocolate?
Lucy Parissi says
You can but it may be too sweet. Maybe use half milk and half dark?
Nanette says
This cake has always been my favorite! I was a school cook for 20 years in the US. I never used coffee in my recipe and melted butter and cocoa for the icing, but other than that everything in the recipe is the same except I used large amounts of ingredients. Feeding 900 students makes a big difference!
Jessica Berry says
Hi, I’m looking to make this on Friday and in the blog it says half caster sugar and the recipe says half granulated. Does it matter which is used?
Thanks
Lucy Parissi says
Hi Jessica you can make it with either, the brown sugar will give it more flavour. Both caster and granulated can be used no problem
Jessica Berry says
Thank you!
Rukshana Aktar says
Hi I just wanted to know if the tray bake can be kept in the fridge after the frosting has been put on it?
Lucy Parissi says
No it can be kept at room temperature in a covered container. If you put it in the fridge after slicing it will dry out x
Rukshana Aktar says
Thank you for responding back. I’ve made it a few times now and everyone has loved it!
Mei says
Hi, I was wondering whether you can freeze the frosting? I made this cake today but there was a lot of leftover frosting.
Lucy Parissi says
I haven’t tried to but I think it might work. Freeze in an airtight container or bag (leave a little space for it to expand). When you are ready to use your frosting, thaw it overnight inside the refrigerator. Before piling it on your cake, knead the thawed frosting with a spoon or give it another stir or a whip for a uniform consistency and you’re ready to go.
Willem Dekorte says
Dear all that is holy ! I have just made this cake for my wife’s birthday, wow !!! What a cake , the nicest chocolate cake I have ever made and eaten!!
Thank you
Will
Lucy Parissi says
Thank you for your wonderful comment and happy birthday wishes to your wife ❤️
Ali M says
Hi, How long will the frosting keep if I make it in advance, and do you think it has enough structure to hold its shape if piped?
Lucy Parissi says
It keeps for a few days keeping its shape (spread on the cake) but if you put it in the fridge it hardens and I don’t think it keeps as well
Margaret says
The Biscoff Traybake and the chocolate traybake, can I freeze them in portions?
Lucy Parissi says
Yes you can. Thaw in the fridge before serving ❤️
N says
I think your metric weights are off as your flour weighs less than your sugar in metric… it’s the opposite in cups
I’ve increased the sugar a bit more so its a little closer to your quantity of flour
Lucy Parissi says
The metric weights are accurate as I cook in metric. The cup weights are slightly less accurate in general (compared to using scales) but I have checked them and the recipe card is correct
N says
Great, thanks for checking! I’ll give the metric version a go.
Rads says
Hi, I was thinking of making a Terry’s Chocolate Orange version of this. If I add grated rind of 2 oranges and chopped choc orange into the batter mix do you think that would work? Also if I melt 175g of choc orange for the buttercream instead of dark choc chips, would that work too? Thank you for your help on this 🙂
Lucy Parissi says
Absolutely! I have a chocolate Orange cake you can look at but all this sounds great
Nic says
Thanks for sharing, this cake looks amazing and yummy 🙂