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Mars Bar cakes made with Rice Krispies and topped with milk and white chocolate
15Prep Time

Mars Bar Cake Recipe

Quick and easy

58 Reviews

About our Chocolate Mars Bar Cake recipe:

The humble Mars Bar Slice is definitely a retro childhood favourite and a fantastic rainy day bake to make with the family (no matter what their age). A chewy gooey cereal base blended with melted Mars Bars and topped with milk chocolate and white chocolate swirls - what's not to love?

Here's how to make Mars Bar Cakes with minimal fuss and maximum flavour. 

15Prep Time


  1. Step 1:

    Prepare a 20cm square baking tin, by lightly greasing it and lining it with baking paper.

  2. Step 2:

    In a heatproof bowl, heat the butter, golden syrup and 3 of the chopped Mars Bars until they have melted. Don't worry if the Mars Bars do not full melt at this point. 

  3. Step 3:

    Add the Rice Krispies into the bowl and stir in with the remaining Mars Bar.

  4. Step 4:

    Pour the mixture into the baking tin and press down firmly (we used a potato masher for this)

  5. Step 5:

    In another heatproof bowl, melt the milk chocolate, stirring until smooth, then pour over the top of the Krispie mixture. 

  6. Step 6:

    Moving quickly before the milk chocolate sets, melt the white chocolate and drizzle in lines up and down the surface of the Mars Bar slice. Using a skewer, drag forward and back through the mixture to create a feathered effect.

  7. Step 7:

    Place the baking tin in the fridge to chill and set. Remove a little while before you plan to serve so that it is easier to cut into squares.


    • 100g Butter (unsalted, softened)
    • 4 Mars Bar 40g size (chopped)
    • 1 1/2 tbsp Silver spoon golden syrup
    • 150g Rice krispies
    • 350g Milk chocolate
    • 50g White chocolate


  • 20cm square baking tin
  • Parchment paper

Nutritional Information

per 50g
  • 262cal Energy
  • 15g Fat
  • 8.7g of which Saturates
  • 29g Carbohydrates
  • 22g of which Sugars
  • 2.9g Protein
  • 0.21g Salt

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