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Chocolate Traybake Cake

Chocolate Traybake Cake

Easy recipe for chocolate traybake cake, also known as a chocolate sheet cake, topped with a luxurious chocolate buttercream
Course Dessert
Cuisine British
Keyword Cake
Servings 12
Calories 625kcal
Author thebakingexplorer


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


  • 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


  • 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.
If you want to make this cake in a 9" square tin you will need:
  • 170g Butter or baking spread
  • 170g Light brown soft sugar
  • 3 Large eggs
  • 1 tsp Vanilla extract
  • 170g Self raising flour
  • 38g Cocoa powder
  • Scant ¼ tsp Baking powder
  • Scant ¼ tsp Bicarbonate of soda
  • 56ml Milk
  • 75g Choc chips


Calories: 625kcal | Carbohydrates: 70g | Protein: 7g | Fat: 38g | Saturated Fat: 24g | Polyunsaturated Fat: 2g | Monounsaturated Fat: 10g | Trans Fat: 1g | Cholesterol: 139mg | Sodium: 296mg | Potassium: 270mg | Fiber: 4g | Sugar: 52g | Vitamin A: 1058IU | Vitamin C: 0.03mg | Calcium: 68mg | Iron: 3mg