Mars Bar slices really are the best ever retro treat, aren't they? With the promise of something sticky, chewy and chocolatey in every single bite you know you're on to a winner. This super quick and easy Mars Bar Slice has it all!
For this recipe, you will need: butter, golden syrup, Mars Bars, Rice Bubbles (Rice Krispies, Rice Pops), milk chocolate and a lined baking pan. I use a 20-cm square pan.
Best Ever Retro Treat
The humble Mars Bar Slice holds a special place in my heart. It reminds me of cooking with my nana and they are something I always made with my own children when they were little.
The taste of them takes me straight back to the 80s - school fetes and picnics.
They are inexpensive and very quick to make - despite the fact I do A LOT of baking Mars Bar slices are still one of my favourite treats to have around the place.
Why Are Mars Bar Slices Awesome?
- Simply melt, mix and refrigerate. You could make them with your eyes closed.
- Chances are you'll have most of the ingredients readily available to make these delicious mars bar slices.
- They are no-bake.
- There an amazing 'emergency bake' - unexpected bake sale? Make a batch of Mrs Bar Slice
- Making your own is much cheaper than buying Kellog's Rice Krispie Squares. And they taste better!
Since I've been making Mars Bar slices a long time I have noticed that as the years have gone by I've needed to buy more Mars bars to accommodate my recipe.
Mars Bars are definitely getting smaller along with Cadbury Creme Eggs and Quality Street to name a couple of examples.
However, they are still pretty cheap to buy in multipacks but bear in mind that the multipack version are a different size to the ones you can buy singularly - 39.4g as opposed to 51g.
I normally pick them up when it's 4 bars for £1 so it works out cheaper that way.
When I unpack the shopping in front of the kids and the Mars Bars topple out, they know they're in for a treat. These little squares honestly go down so well, if you've never tried one I think you'll love them as much as we do.
Can I make a Mars Bar Slice in my Thermomix?
Yep - simply add the butter and syrup to the Thermomix along with 4 chopped Mars bars. Stir through the Rice Bubbles then transfer to a lined baking pan and refrigerate until set.
How long do Mars Bar Slices keep for?
If it's really warm you can keep them in the fridge to stop the chocolate melting but they might be a bit hard eaten straight from the fridge, so take them out in advance.
Alternatively, these Mar Bar Slices will keep in an airtight container in a cool dark place for 4-5 days.
Can you freeze Mars Bar Slice?
Yes, you can. People often worry that the rice bubbles will go soft but that is not the case. Mars Bar Slices can be frozen for one month. To defrost, remove from the freezer and leave them out for one hour to thaw prior to eating. They can also be eaten straight from the freezer if your teeth can bear it!
Can you make Mars Bar Slice with Coco Pops?
The answer is a resounding yes. I've done it myself many times, just swap out the Rice Bubbles for the same quantity of Coco Pops.
How to make the best ever Mars Bar Slice
I made a short video of the steps for this recipe. You can see it in the recipe card below – hope it helps.
- Time needed: 10 minutes
- Makes 20 squares
Making Mars Bar Slices couldn’t be easier, just follow these simple steps.
- In a saucepan, melt ¼ cup of unsalted butter and 2 tablespoons of corn syrup (golden syrup).
- Chop 4 mars bars (from multipack - approx ⅔ cup or 150g) and add them to the saucepan to melt.
- Once melted add 3 cups of Rice Bubbles and mix to combine.
- Chop a further 4 mars bars (from multipack - approx ⅔ cup or 150g) and add them to the Rice Bubbles mixture, folding to combine.
- Transfer the mixture to a lined baking pan and use the back of a wooden spoon to flatten.
- Melt 8.5 ounces (250g) milk chocolate and pour over the top.
- Leave to set in the fridge and when the chocolate has hardened, slice into squares.
Mars Bar Slice Step by Step Images
That's all there is to it. Making Mars Bar Slices is so quick and easy but the final result is fantastic.
For more super quick and easy sweet treat recipes, why not check these out:
- Nutella Crepes - Ready in 10 minutes
- Healthy Fruit and Nut Chocolate Thins
- Candy Cane Hearts with White Chocolate Centres
- Marshmallow Pops
If you loved this recipe please give me a 5-star rating below and leave a comment.
Best Ever Mars Bar Slice
Your go to Mars Bar Slice recipe. Just 5 simple, everyday ingredients make the sweet treat your entire family will love!
- 55g (¼ cup) unsalted butter
- 2 tbsp golden syrup/corn syrup
- 8 Mars Bars (from a multipack)
- 100g (3 cups) Rice Bubbles, Rice Pops, Rice Krispies
- 250g (8.5 ounces) Milk Chocolate, I use Cadburys
- Line a 20cm square baking tin with baking paper.
- In a saucepan, melt the butter and corn/golden syrup.
- Chop 4 mars bars and add them to the saucepan to melt.
- Once melted add Rice Bubbles and mix to combine.
- Chop a further 4 mars bars and add them to the Rice Bubbles mixture, folding to combine.
- Transfer the mixture to the prepared baking tin and use the back of a wooden spoon to flatten.
- Melt the milk chocolate and pour over the top. Leave to set in the fridge and when the chocolate has hardened, slice into squares.
- You can use any brand of Rice Bubbles, it doesn't matter if they are the supermarket own version.
- Mars Bar Slices freeze really well.
- Store in an air tight container for 5 days.
Nutrition Information:Yield: 20 Serving Size: 1 grams
Amount Per Serving: Calories: 175Total Fat: 6gSaturated Fat: 3gUnsaturated Fat: 0gCholesterol: 5mgSodium: 41mgCarbohydrates: 12gSugar: 8g
Best recipe for Mars Bar Slice I've found. Thanks!
Wow, thank you for the comment! Love Mars Bar Slices so much!
Making these for half term :)
Can I please ask what size Mars bars you’re using?
Hi Toni, they were from a multipack - They are 39.4g each as opposed to the larger ones you buy on their own which are 51g. Hope that helps!
Thanks for the prompt reply Amy! Can I also ask what size tin you use?
No probs! I used a 20cm square tin.
Best recipe I have come across and the one I will stick with from now on. I always find your recipes to be reliable so was delighted to find this. Used a multiple of Titan bars from Aldi, they are 39g so used 6 and it worked perfectly! Thank you!
Thanks for the titan tip