Mary Berry Mars Bar Cake Recipe

This Mary Berry Mars Bar Cake Recipe is the ultimate retro “fridge cake,” transforming a few simple confectionery aisle staples into a chewy, caramel-infused traybake. Unlike standard chocolate crispy cakes that just use cocoa, this recipe melts down whole Mars bars to create a thick, nougat-rich binding that coats every grain of puffed rice, finished with a solid layer of milk chocolate for a satisfying snap. It is a no-bake masterpiece perfect for children’s parties or a nostalgic afternoon treat.

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Mary Berry Mars Bar Cake Ingredients

• 3 Standard Mars Bars (approx. 150g – 175g total): Chopped into small slices. The nougat and caramel in the bars act as the sugar and glue for the cake.
• 100g (4 oz) Unsalted Butter: Cubed. This melts with the chocolate bars to create a rich, glossy sauce. Using unsalted allows the sweetness of the caramel to shine without becoming cloying.
• 1 tablespoon Golden Syrup: This is the secret ingredient often found in Mary’s traybakes; it adds a glossy finish and prevents the mixture from setting too rock-hard.
• 100g (4 oz) Rice Krispies (Puffed Rice Cereal): The classic base. You can also use cornflakes if you prefer a sharper crunch.
• 200g (7 oz) Milk Chocolate: Good quality, broken into pieces. This forms the thick layer on top.
• 25g (1 oz) White Chocolate (Optional): For drizzling/feathering on top to give it that professional finish.

How To Make Mary Berry’s Mars Bar Cake

1. Prepare the Tin: Grease a 28cm x 18cm (11in x 7in) rectangular traybake tin or a square 20cm (8in) tin and line the base and sides with non-stick baking parchment.
2. Melt the Base: Place the chopped Mars bars, cubed butter, and golden syrup into a heatproof glass bowl. Place the bowl over a saucepan of gently simmering water (bain-marie), ensuring the bottom of the bowl does not touch the water.
3. Stir and Smooth: Stir the mixture occasionally. The chocolate and caramel will melt first, while the nougat takes longer. Keep stirring gently until you have a smooth, thick, chocolatey sauce. Do not let it boil or the nougat will become grainy.
4. Mix the Cereal: Remove the bowl from the heat. Pour the Rice Krispies into the chocolate mixture. Stir gently but thoroughly until every single grain of rice is coated in the Mars bar sauce.
5. Press: Tip the mixture into the prepared tin. Using the back of a metal spoon, press the mixture down firmly to create a dense, even layer. Make sure to push it right into the corners.
6. Melt the Topping: Melt the 200g of milk chocolate in a clean bowl over simmering water (or in the microwave in short bursts).
7. Top and Feather: Pour the melted milk chocolate over the Rice Krispie base and spread it evenly with a palette knife. If using the white chocolate, melt it separately, drizzle lines across the wet milk chocolate, and drag a cocktail stick through the lines to create a feathered effect.
8. Chill: Place the tin in the fridge for at least 1 to 2 hours, or until the chocolate topping is completely set and hard.
9. Slice: Remove from the tin using the parchment paper. Use a sharp knife (dipped in hot water) to slice into squares or fingers.

Recipe Tips

• The Nougat Factor: Mars bars contain fluffy nougat which is resistant to melting. Be patient. If you overheat it, the mixture will separate and look oily. Low and slow is the key.
• Slicing Without Cracking: The solid chocolate top can crack when cut cold. To prevent this, score the chocolate lines lightly with a knife about 15 minutes into the chilling time, or let the cake sit out of the fridge for 20 minutes before cutting.
• Compacting: The success of this cake relies on how hard you press the Rice Krispies into the tin. If you don’t press firmly enough, the squares will fall apart when you pick them up.
• Golden Syrup Substitute: If you can’t find Golden Syrup, liquid glucose or mild honey works as a binding agent, though the flavor will change slightly.

What To Serve With Mars Bar Cake

• Cold Milk: A classic pairing for a sweet, crunchy treat.
• Tea: The bitterness of tea balances the extreme sweetness of the caramel.
• Fresh Strawberries: The acidity of the fruit helps cut through the richness of the chocolate.

How To Store Mars Bar Cake

• Refrigerate: In warm weather, these must be kept in the fridge or the Mars bar binding will soften and become sticky.
• Airtight Container: They will keep in a sealed container in the fridge for up to 1 week.
• Freezing: You can freeze the squares separated by parchment paper for up to 1 month. Thaw in the fridge.

Mars Bar Cake Nutrition Facts

• Calories: ~290 kcal
• Fat: 14g
• Carbohydrates: 38g
• Protein: 3g
• Nutrition information is estimated per square based on 12 servings.

FAQs

Try More Recipes:

• Mary Berry Tunis Cake Recipe
• Mary Berry Golden Syrup Cake Recipe
• Mary Berry Cut And Come Again Cake Recipe