Mary Berry Chocolate Tray Bake​ Cake Recipe

The ultimate Mary Berry Chocolate Tray Bake Cake is made with a famously quick and easy all-in-one sponge that results in a perfect cake every time. This recipe creates a soft, moist, and wonderfully light chocolate sponge covered in a simple chocolate fudge icing. It’s the definition of a no-fuss, crowd-pleasing treat. Perfect for children’s parties, school bake sales, or simply as an easy weekend treat, this foolproof recipe makes a generous 24 squares.

Mary Berry Chocolate Tray Bake Cake Ingredients

For the Chocolate Sponge:

• 225g (1 cup) unsalted butter, softened, or a soft baking spread
• 225g (1 cup plus 2 tbsp) caster (superfine) sugar
• 4 large free-range eggs
• 275g (2 cups plus 2 tbsp) self-raising flour
• 2 teaspoons baking powder
• 50g (1/2 cup) unsweetened cocoa powder
• 4 tablespoons boiling water

For the Chocolate Icing:

• 75g (1/3 cup) unsalted butter
• 2 tablespoons milk
• 200g (1 3/4 cups) icing (powdered) sugar, sifted
• 40g (1/3 cup) unsweetened cocoa powder, sifted
• Sprinkles or chocolate shavings, to decorate

How To Make Mary Berry Chocolate Tray Bake Cake

1. Preheat oven and prepare tin: Preheat your oven to 180°C (160°C Fan / 350°F). Grease a standard tray bake tin, approximately 30 x 23 cm (12 x 9 inches), and line the base with baking parchment.
2. Prepare the cocoa paste: In a small bowl, mix the 50g of cocoa powder with the 4 tablespoons of boiling water. Stir until you have a smooth, glossy paste. Set this aside to cool for a few minutes.
3. Combine the cake ingredients: In a large bowl, place the softened butter or spread, caster sugar, eggs, self-raising flour, and baking powder. Beat with an electric mixer until all the ingredients are well combined.
4. Add cocoa and bake: Add the cooled cocoa paste to the batter and beat again until it is fully incorporated and the batter is an even chocolate colour. Spoon the mixture into your prepared tin and spread it out evenly, right into the corners. Bake for 30-35 minutes, or until the cake is well-risen and springs back when lightly pressed.
5. Cool the cake: Let the cake cool completely in the tin on a wire rack.
6. Make the chocolate icing: To make the icing, melt the 75g of butter and 2 tablespoons of milk in a small saucepan over a low heat. Remove from the heat and add the sifted icing sugar and sifted cocoa powder. Beat with a wooden spoon until the icing is smooth and glossy.
7. Ice and decorate: Pour the warm icing over the top of the cooled cake, still in its tin. Gently tilt the tin and use a palette knife to spread the icing evenly to the edges. Scatter over your chosen sprinkles or chocolate shavings before the icing sets.
8. Cut and serve: Once the icing has completely set, you can lift the cake out of the tin using the parchment paper and cut it into 24 squares.

Recipe Tips

• Blooming the cocoa powder: The simple step of mixing the cocoa powder with boiling water before adding it to the cake batter is a classic Mary Berry technique. It dissolves the cocoa and “blooms” it, which helps to release a much deeper, richer chocolate flavour.
• Line the tin properly: For easy removal, grease the tin and then place a sheet of baking parchment that covers the base and comes up the two long sides. This creates handles that allow you to lift the entire cake out easily once it’s cooled.
• Don’t overbake: Tray bakes are thinner than layer cakes and cook more quickly. To avoid a dry cake, start checking for doneness at the 30-minute mark. It’s ready when it’s springy to the touch.
• Ice the cake in the tin: The easiest and neatest way to ice a tray bake is to leave it in its tin. This contains the icing and allows you to spread it right to the edges for a professional finish.

What To Serve Chocolate Tray Bake Cake

This chocolate tray bake is the epitome of a simple, self-contained treat. It’s designed to be cut into squares and eaten straight from your hand, making it the perfect fuss-free option for parties, picnics, and bake sales. It needs no accompaniment other than a glass of cold milk for the kids or a welcome cup of tea for the adults.

How To Store Chocolate Tray Bake Cake Leftovers

• Store: To keep the cake fresh, store it in its tin, covered tightly with foil or plastic wrap. You can also transfer the squares to an airtight container. It will stay lovely and moist at room temperature for up to 3 days.
• Freeze: This cake freezes exceptionally well, either as a whole slab or in individual squares. Wrap it well in a double layer of plastic wrap and then a layer of foil. It can be frozen for up to 3 months. Thaw at room temperature before enjoying.

Mary Berry Chocolate Tray Bake Cake Nutrition Facts

Serving Size: 1 square (1/24th of cake)

• Calories: 225 kcal
• Total Fat: 12g
• Saturated Fat: 7g
• Cholesterol: 45mg
• Sodium: 160mg
• Total Carbohydrate: 26g
• Dietary Fiber: 1g
• Sugars: 19g
• Protein: 3g

Frequently Asked Questions

• What size is a standard tray bake tin? A standard British tray bake tin is typically around 30 x 23cm (12 x 9 inches) and about 4cm deep. It’s a very common and versatile piece of kitchen bakeware.
• My icing is too thick/thin. How can I fix it? This icing is very forgiving. If it seems too thick to spread, add another teaspoon of milk and beat again. If it seems too thin, simply add a little more sifted icing sugar until it reaches the desired consistency.
• How do I get perfectly neat slices? For the cleanest cuts, it’s essential that both the cake and the icing are completely cool and set. Use a large, sharp knife and press down firmly. For extra precision, wipe the knife blade clean with a piece of hot, damp kitchen towel between each cut.
• Can I add chocolate chips to the cake? Yes, for an extra chocolatey hit, you can fold in about 150g of milk or semi-sweet chocolate chips into the batter after the cocoa paste has been incorporated.