Cakes and Cupcakes

Easy Chocolate Cake Traybake

Say hello to the BEST Chocolate Traybake – a.k.a Chocolate Sheet Cake! This moist chocolate cake topped with decadent chocolate

  • Serves 15 -20 slices
  • Prep 15 minutes
  • Cook 35 minutes
  • Total 50 minutes

Chocolate

Jump to the recipe
Easy Chocolate Cake Traybake
close up on a chocolate sheet cake covered in chocolate frosting and sprinkles and cut into squares

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 as pie, 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 🙂

A square slice of chocolate sheet cake with chocolate frosting and colorful sprinkles sits on a white plate, with a few crumbs scattered around.

Here’s What You’ll Need

  • Plain flour (all purpose flour) plus baking powder and bicarbonate of soda.
  • Sugar: ideally a mix of granulated and light soft brown sugar
  • Cocoa powder: use the best quality unsweetened cocoa powder
  • Espresso powder: this enhances the chocolate flavor but is completely optional
  • Three large eggs at room temperature
  • Softened unsalted butter or margarine
  • Buttermilk or milk soured with a little lemon juice

Chocolate Frosting

  • Softened unsalted butter (do not use margarine in the frosting)
  • Sifted powdered sugar
  • Cocoa powder
  • Milk, heated in the microwave for 30 seconds until a little warm
  • Chocolate: use good quality semi-sweet chocolate chips (and while you are at it, take a look at my Dubai Chocolate Bar Recipe!)
Easy Air Fryer Bakes cookbook cover

How to Make My Chocolate Traybake Cake

Make the Cake

  1. Make sure your ingredients are at room temperature. Put the flour, sugar, cocoa powder, baking powder, baking soda and espresso powder in a large mixing bowl (or the bowl of your stand mixer). Use a balloon whisk or fork to stir so they are combined.
  2. Add the softened butter, eggs and soured milk and beat 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!
  3. Transfer the batter to a lined sheet pan (9×13 inches), level 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.
  4. Cool the cake in the tin for 10 minutes then use the overhanging paper to carefully lift onto a wire rack to cool completely.
Four-step chocolate sheet cake-making process: Top left, mixing dry ingredients; top right, adding butter and eggs; bottom left, stirring thick chocolate batter; bottom right, smoothing batter in a pan with a spatula.

Make Frosting, Decorate and Serve!

  1. 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.
  2. 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!
  3. 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!
  4. 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).
  5. Add sprinkles, chocolate buttons, M&Ms or leave plain. When you are ready to serve, slice the cake using a serrated knife, wiping the knife clean between each slice.
Left side shows a bowl with chocolate batter being mixed for a delicious Chocolate Traybake. Right side shows a hand spreading rich chocolate frosting on the cake with a spatula, creating a perfect treat.
An overhead view of chocolate sheet cake (chocolate traybake) cut into neat squares, each topped with chocolate frosting and colorful sprinkles, with a few pieces missing. A knife and bowls of extra sprinkles are nearby on the gray surface.

Storing and Freezing

  • This chocolate cake will keep for 2-3 days at room temperature in an air tight container or cake carrier but it is best eaten when fresh.
  • To freeze the cake unfrosted: allow the cake to cool down. Wrap tightly in a layer of plastic wrap and a layer of foil. Place in a suitable container or bag, label with the date and freeze for up to three months. Thaw the cake in the refrigerator overnight. Return to room temperature before adding any frosting.
  • How to freeze a frosted chocolate cake: assemble the cake and place in the refrigerator for 30 minutes so that frosting can harden. Wrap the cake in plastic wrap, then foil. Place the cake, whole or in slices, it in a freezer-safe container, date and freeze for up to 3 months.  Thaw in the fridge overnight and serve at room temperature.
Chocolate cake with sprinkles on a baking sheet.

My Most Popular Cake Recipes

Cake

School Cake (Sprinkle Vanilla Tray Bake)

Cake

Lemon Drizzle Traybake

Cake

Air Fryer Cake

Cake

Fresh Berry Cake

HAVE YOU MADE MY CHOCOLATE CAKE TRAYBAKE RECIPE? Please leave a rating, post a photo on my Facebook page, share it on Instagram, or save it to Pinterest with the tag #Nusde and make my day!

You might also like my Chocolate Banana Cake.

Recipe

Chocolate Traybake

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!

  • Serves 15 -20 slices
  • Prep 15 minutes
  • Cook 35 minutes
  • Total 50 minutes

Ingredients

  • ¾ cup (180ml) milk
  • 2 tbsp lemon juice (to sour milk)
  • 2 ½ cups (300g) all-purpose flour ((= plain flour))
  • ½ cup + 2 tbsp (60g) cocoa powder (natural, unsweetened)
  • 1 ⅔ cups (330g) sugar (granulated or light brown sugar)
  • 1 tbsp espresso powder ((optional))
  • 1 tbsp baking powder
  • ½ tbsp baking soda ((= bicarbonate of soda))
  • ½ tsp salt
  • ⅞ cup (200g) unsalted butter (softened)
  • 3 large eggs

Chocolate Frosting

  • 1 cup (175g) semi sweet chocolate chips (melted and cooled)
  • 2 cups (240g) powdered sugar ((= icing sugar))
  • 6 tbsp cocoa powder (natural, unsweetened)
  • ⅔ cup (150g) unsalted butter (softened)
  • ½ cup (120ml) milk (slightly warm)

To decorate

  • sprinkles or candy of your choice

Method

Make the cake

  1. 1

    Preheat the oven to 340°F (170°C). Mist a 9x13inch rectangular pan with cake release and line with baking paper.

  2. 2

    Combine the milk and lemon juice in a measuring jug and let stand for 5 minutes to sour the milk.

  3. 3

    Put the flour, cocoa powder and sugar in large bowl. Add the espresso powder if using, baking powder, bicarbonate of soda and salt and mix together using a balloon whisk.

  4. 4

    Add the butter, eggs and soured milk.

  5. 5

    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.

  6. 6

    Transfer the batter in the prepared tin and level. Transfer the batter into the prepared sheet pan, level and bake for 35 -40 minutes.

  7. 7

    Check the cake is done by inserting a skewer in the middle – it should come out clean, the cake should be well risen golden and springy to the touch. Cool the cake on a wire rack before frosting.

Chocolate Frosting

  1. 8

    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.

  2. 9

    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.

  3. 10

    Add the softened butter and start mixing on low speed, gradually adding the milk until the frosting is well combined.

  4. 11

    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

  1. 12

    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).

  2. 13

    Add sprinkles, chocolate buttons, smarties or leave plain. Slice the cake using a serrated knife, wiping the knife clean between each slice.

Notes

This chocolate sprinkle cake will keep for 2-3 days at room temperature but it is best eaten when fresh. Alternatively you can freeze the cake for up to three months. Wrap tightly in a layer of plastic wrap, then foil. Place in a freezer-safe container, label with the date and consume within three months. Thaw overnight in the fridge and serve at room temperature.

Equipment

  • 9×13 rectangular cake tin
  • Electric hand mixer
  • Digital scales
  • Stand Mixer
  • Offset spatula / Palette knife
  • Cake release

Nutrition

  • Calories490 kcal
  • Carbohydrates67 g
  • Protein6 g
  • Fat24 g
  • Saturated Fat7 g
  • Cholesterol36 mg
  • Sodium439 mg
  • Potassium256 mg
  • Fiber3 g
  • Sugar47 g
  • Vitamin A941 IU
  • Vitamin C1 mg
  • Calcium94 mg
  • Iron2 mg