Mars Bar Squares

  • Total Time

  • Serves


The humble Mars Bar Cake 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? 


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

  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. 

    • 100g Butter (Unsalted, Softened)
    • 3 Mars Bars (Chopped)
    • 1½ tbsp Silver Spoon Golden Syrup
  3. Add the Rice Krispies into the bowl and stir in with the remaining Mars Bar.

    • 150g Rice Krispies
    • 1 Mars Bars (Chopped)
  4. Pour the mixture into the baking tin and press down firmly (we used a potato masher for this)

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

    • 350g Milk Chocolate
  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.

    • 50g White Chocolate
  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.

Let's Bake

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  1. 5 star rating

    Delicious. Easy to make with kids and all the family loved them.

  2. 5 star rating

    amazing i made them last week

  3. 5 star rating

    Great recipe! This tray bake wasn't around for long! So easy to make.

  4. 5 star rating

    Great recipe! This tray bake wasn't around for long! So easy to make.

  5. 5 star rating

    A great recipe and very moreish. Grandchildren loved making them to take home so made another tray for us fter they'd gone.!

  6. 5 star rating

    Lovely really recommend

  7. 5 star rating

    I made them for some elderly people from my church as we are in lockdown. I take something different every week . Thumbs up thank you

  8. 5 star rating

    This recipe is one of the best we have tried. Some do not use syrup and they do not stick together the same. It seems to us that using the potato masher is also important otherwise I think the rice krispies come apart more easily. A delicious turnout every time. My husband makes the best one.

  9. 4 star rating

    I use 2 multi packs of mars bars, so much smaller than when I was growing up. Also use 2 heaped tablespoons of Lyle golden syrup (this stops the krispies being too soft) & a little Vanilla Essence. For the person whose Rice Krispies went soft, remember to push and firm down the Rice Krispies with the back of a metal spoon into the container. I make 2 round cake tins, not as deep as the squares, and 1 lot of squares with this recipe.

  10. 5 star rating

    Made these for my granddaughter to take into her colleagues in hospital everyone absolutely loved them !!

  11. 5 star rating

    I have been making Mars Bar Cake for years, without the white chocolate as this makes them taste more like Mars Bars and less sweet for us. For added flavour I also add 1 teaspoon of Vanilla Essence, you really notice the difference. You definitely need to use 8 of the smaller mars bars (2 multi packs of 4) to cover the Rice Krispies properly, because they are half the size they were when I first made this recipe in my childhood. I also use 2 - 3 tablespoons of Golden Syrup. Very important to push the mixture down hard with the back of a metal spoon, makes them even more delicious.
    Just made a Mars Bar Cake for my daughters 35 birthday, as always, everyone loved them.

  12. 5 star rating

    We love them we don’t have a kitchen so they are really easy and delicious 😋

  13. 5 star rating

    Made them for ICU nurses & they absolutely loved them

  14. 5 star rating

    so easy to make and so delicious I will be making them again soon!

  15. 5 star rating

    This was perfect for a family night in I would definitely recommend to everyone

  16. 5 star rating

    we have made these 4 times since lockdown lol cant get enough! thanks for the great recipe

  17. 5 star rating

    Make this a lot only use 200g of chocolate for the top it’s enough and cheaper

  18. 5 star rating

    Hi , this is my third time making them and we love them , but for some reason the rice Krispies went a bit soft , fresh box so that's not the reason, can any one explain where I went wrong ???

  19. 5 star rating

    I mesd up a bit i forgot to heat the butter syrup and mars bars but we saved it

  20. 5 star rating

    What is the best way to store the Mars Bar squares in the fridge or can they be left out in an airtight container?

  21. 5 star rating

    These were so yummy everyone in the family enjoyed them...added made more Rice Krispies so that the base wasn’t too ssweet and lighter. Will definitely be making again...bookmark!

  22. 5 star rating

    all the kids love them so easy to lour them form there familys thank you.

  23. 5 star rating

    so easy to make, taste amazing!!

  24. 4 star rating

    Really good recipe guys

  25. 4 star rating

    Hi, wondering if someone could help. Seeing that all the choc mars tiny now. Do I still use 4 mars bars or should I up to like 6 or more? There 39 grams the ones I have


  26. 5 star rating

    amazing, i made one batch for fun and i’ve had to make loads more as everyone loves them. highly recommend, also a great way to keep you busy during lockdown 👍

  27. 5 star rating

    It’s okay

  28. 5 star rating


  29. 5 star rating

    This recipe is my childhood! I love making this for my kids

  30. 5 star rating

    As mars bars come in various sizes can I ask what weight of the mars bars is? Multi pack ones are generally smaller.

  31. 4 star rating

    Best recipe out there for Mars Bar Cakes!! but I would advise maybe 100g rice krispies instead of 150g as there wasn't enough cohesion.

  32. 5 star rating

    So good they won the bake sale!

  33. 5 star rating

    Made this for a cake sale and it was the first to disappear! I doubled the recipe as Ruth Street suggested, but should have trebled it as there was none left to eat at home! I have used supermarket own brand versions of mars bars and it was just as delicious. Rather than melting the white chocolate for the topping I have also decorated with a scattering of white chocolate shavings. Now making a batch for a birthday party. Great recipe.

  34. 5 star rating

    I made these for a cake sale at work, I should have doubled the recipe as they were very popular!

  35. 5 star rating

    Made them as gifts and worked really well.

  36. 5 star rating

    So easy to make and a definite winner!

  37. 5 star rating

    I have made these Mars bar squares numerous times now and they are so easy to make and everybody loves them!
    Definitely recommend them. Delicious!

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