Mars Bar Slice Recipe

Mars Bar Slice. A retro treat that's no-bake and easy to make. Crisp chocolate (a layer or dark, then a layer of milk chocolate) on top of a chewy caramel crispy base.

Mars bar slice is a treat I remember making with my mum when I was little. We had such fun playing about in the kitchen making treats like these, truffles and chocolate krispie cakes. There was always chocolate involved.

It's funny, as a child I was offered chocolate and sweets regularly. but I didn't eat a lot and a quarter of sweets would last me a week.

I decided not to go down this route with Cooper. He has chocolate occasionally, but never sweets. We never give him a bar or packet of chocolate to work his way through either, it's more a sharing thing and the great thing is although he loves chocolate, especially dark chocolate, he'll often say no to it and isn't desperate for it like some children I see hounding their parents.

I know there's debate about this and some say it causes problems in later life, but I believe the best thing to do with food, any food, but especially unhealthy food, is let children try it but not make a big fuss about it. Making a fuss gives it too much importance and it can become an emotional issue or a power struggle. 

A lot of our food indulgence is habit and if you don't create this habit, your child won't be desperate to feed the habit beast. It's a good thing for us to think about as adults too. Occasional treats are so much more enjoyable, like an ice cream cone on a sunny day. I should listen to my own advice. Ahem!

Mars Bar Slice. A retro treat that's no-bake and easy to make. Crisp chocolate (a layer or dark, then a layer of milk chocolate) on top of a chewy caramel crispy base.

I published this recipe years ago, but I've since realised that Mars Bars, while still delicious, are getting smaller as time goes on so the recipe needed to be tweaked. I also top the bar with a layer of milk chocolate, which I also make the main mixture with, then top it with a layer of dark chocolate and a slice of Mars Bar for decoration. A crisp bite of chocolate through to a chewy chocolate and caramel crispy base, absolutely fabulous!

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Mars Bar Slice
A retro no-bake chocolate slice made with melted Mars Bars and Rice Krispies. An easy treat that's super easy to make and way too easy to eat..
  • 6 Mars Bars, plus 2-3 for decoration
  • 5 tbsp golden syrup
  • 200g/1 cup raisins
  • 75g/3 cups Rice Krispies
  • 300g Cadburys Milk Chocolate
  • 200g dark chocolate
1. Line a brownie tray. I use foil-backed greaseproof paper for ease and my tray is 20x30cm and 3 cm deep.2. Cut 6 Mars Bars into chunks and melt gently in a pan with the golden syrup.3. While the mixture is melting, measure the Rice Krispies into a large bowl.4. Pour the mixture over the Rice Krispies and mix well then press into your baking tray. Put in the fridge while you work with the chocolate.5. Melt the milk chocolate in a bain marie (a bowl over simmering water). Make sure the bottom of the bowl doesn't touch the water or the chocolate may seize.6. Spread the chocolate smoothly across the crispy base, then pop in the fridge to set.7. Once the chocolate has set, melt the dark chocolate in the same way and spread on smoothly. Top evenly with slices of Mars Bar for decoration and chill.8. My Mum's tip is to score the chocolate while it is half set and still a little soft. It cuts through easier once it's set.9. Cut into slices and enjoy!
Total time:
Yield: Makes 24 slices

This batch was made for my Baking Club. The theme was retro, so I thought back to my childhood. Yes I'm old enough for my childhood treats to be retro. My friend Stuart (Cakeyboi) was hosting this month and he chaired the quiz. My team won! Yay!!!!!!

Oh and I didn't write this post in association with Mars, it's what my Mum used in her recipe so I use the same.


  1. I love the idea of these treats, I must make some for our family BBQ

    1. Yes you should. I take it you don't have snow then like some places are having right now, if you are planning a BBQ.

  2. Ahh! I used to make these as a kid but have never thought of making them with my girls. I will have to soon :D x

    1. Oh good I hope you do, they will love them and such fun to make.

  3. Yes! This looks so good. Wish I could come to your baking club!

  4. What a great treat for everyone.

  5. Oh em gee, this looks so so good! Must make this at some point, hubby would love it

  6. THIS. I need to make this so bad! And another cornflake tart... for blog post purposes of course :)

  7. Just made this &'realised that I didn't add the raisins! Completely forgot them as they're only mentioned in ingredients. Maybe if I'd weighed out ingredients 1st I'd have been more on the ball. I'm sure this will disappear just as quick. Easy to make .

    1. Fabulous and I am sure they will still be delicious without that raisins. Hope you enjoy them x


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