Mars bar slice
Mars bar slice is an easy no bake traybake kids will love. With only five ingredients it’s the perfect introduction to baking for little chefs.
Mars bar slice or Mars Bar cake is a bake I remember from my childhood here in the UK, It’s a classic childhood bake, filled with chocolatey goodness and nostalgia. It’s a scrumptious no bake traybake full of chocolate, and a ooey, caramel-y, chocolate-y Rice Crispie base.
It’s such an easy, but delicious recipe, with only 5 ingredients, that anyone can make which is why it’s perfect for children to try. It also makes it perfect for bake sales and sharing with friends.
There’s nothing healthy about it but if you want something really easy to make with your kids then this is a great option. It’s a no bake traybake which means once you’ve melted the mars bars and butter (and you can do this in the mircrowave so there’s no need to use your cooker) you just need to stir it together with the Rice Krispies and leave it to set. It only takes about 10 minutes to make it, so the hardest part of this recipe is waiting for it to set before you can eat it!
The Mars bars we get in the UK (and I believe most of the world) have chocolate, caramel and nougat in them and I think all that extra yumminess makes these super naughty but so so good. In the USA, the equivalent chocolate bar to use to get all the deliciousness is a Milky Way.
If you’re in the UK and want a cheaper alternative try Aldi’s Titan bars, or Lidl’s Caramel bars. They’re the same as Mars bars, so work well in the recipe but for a fraction of the price.
How can kids help make the Mars Bar slice?
As a no bake traybake, this is a really easy treat for kids to make. As well as measuring out the Rice Crispies and other ingredients, they’ll be able to help melt the Mars Bars and butter before mixing it all together. You can melt the Mars bar in your microwave if you have one, so you don’t need to use your cooker if you don’t want to, which is ideal for little kids.
Once your kids have mixed the ingredients together they can help pat it all into your traybake tin, pushing it in to all the corners. Then it’s a simple job of leaving it to set. There’s no baking skills involved, all you need is a little bit of patience.
How many Mars bars should I use?
Mars bars, or in the USA Milky Ways, come in all different sizes. We used 4 of the ‘normal’ sized ones you’ll find in the sweet counter of your local shop. If you have larger or smaller ones, just make sure the total amount comes to at least 200g so you don’t miss out on any of the delicious gooiness.
Should I use Butter or margarine?
For something like this easy traybake you can use either butter or margarine. We’ll tend to use whatever we have more of in the fridge, but both work just as well.
How do you cut the chocolate without it cracking?
The hardened chocolate might crack if you try and cut it straight from the fridge. If you’ve left it in the fridge to set, it’s best to remove it from the fridge about half an hour before you try to cut it, just to allow the chocolate to warm a little bit.
Use a really sharp knife (it’s not a job for little kids), and score the top of the chocolate where you want to cut a few times before you actually cut it.
Why is my Mars bar slice too hard?
If you haven’t melted the Mars bar, butter and syrup mixture enough it might not mix in well to your Rice Crispies. Make sure everything has fully melted and is nice and smooth before you pour it into your mixing bowl.
Why is my Mars bar slice crumbly?
If your slice crumbles apart when you cut it, it’s likely because the Mars bar mixture wasn’t stirred through the Rice Crispies well enough to coat everything. Or perhaps, you didn’t press it into the tin firmly enough. Make sure your kids press the base down well into the edges and corners to that it binds well together.
Can you melt Mars bars in the microwave?
Yes. If you don’t want to melt the Mars bars on the hob, you can melt them in the microwave. Make sure you do it in small intervals, and stir it well between each blast.
How do you store Mars bar slice?
Mars bar slice will keep in an air tight container at room temperature for up to a week. If you want to keep it for longer, or make it ahead of time, you can freeze it (individually wrapped in cling film) for a month or two.
Other no bake treats
If you like this Mars bar slice you’ll love our other easy no bake treats including:
Chocolate cornflake cakes
Tiffin
Rocky road
Rocky road fudge
Chocolate rice krispies
Biscoff millionaires shortbread
Rice Krispie treats
Potato scones
Useful equipment
You might need the following baking tools/gadgets to make this Mars bar slice:
Digital scales
Sauce pan
Measuring cups
Spatula
Mixing bowl
Baking tin
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Difficulty: Easy
Time: 15 minutes plus chilling
Serves: 15
Ingredients
50g (1/4 cup) butter/margarine
1 tbsp golden syrup
4 regular (UK) sized mars bars (approx 200g)
3 cups Rice Crispies/rice bubbles (about 60g)
250g (1 1/2 cups) milk chocolate
How to make the mars bar slice
Get your kids to grease a square 20cm (8 inch) baking tin, and line the base and sides with baking or parchment paper. We find the easiest way of lining a square tin is to cut a strip that fits in one direction, then doing the same in the other direction.
Make the base of the mars bar slice
Measure the butter/margarine (50g) and golden syrup (1 tbsp) out and add to a small pan. Get your kids to roughly chop the mars bars up and then add them to the butter.
This is quite a good chopping job for young kids to practice using a knife as you can use a blunt knife and not worry too much about small fingers. Just get them to chop it roughly, it doesn’t matter if all the pieces are the same size, it’s just to help it all melt in properly. It can get a wee bit sticky though, so maybe have a wet wipe to hand.
Melt everything in the mircrowave or in a small pan on a low heat. Stir it occasionally (or get older children to) until it comes together in a smooth chocolate mixture.
If you’re using the microwave to melt everything, pop it all in a microwavable bowl and zap it for short intervals (30 seconds or so). Take it out and stir it to make sure it melts evenly and doesn’t burn.
Meanwhile get your kids to measure the Rice Crispies (3 cups) out into a large mixing bowl.
Add the melted Mars bar mixture to your mixing bowl.
Mix everything together with wooden spoons or a spatula, so the Rice Crispies are all nicely coated with the melted mars bar.
Pour your mixture into your prepared baking tin and get your kids to press it down with the back of a spoon. We found a metal spoon worked best for this as the mixture didn’t stick to it as much as it did the wooden spoons.
Make sure you push it properly into the corners and edges of your baking tin. If you have another same sized tin, you can press the flat base of that down on top, to really firm up your base and ensure there are no air pockets.
Leave your Mars bar slice aside for at least 30 minutes to set.
Add the chocolate topping
Break the chocolate into small pieces, then melt it in the microwave, at a medium heat, in 30 second intervals. Stir the chocolate in between blasts to make sure it doesn’t burn.
Alternatively, you can melt the chocolate in a bain marie, which is a heatproof bowl set over a pan of simmering water. Melt it nice and slowly, stirring it, until it is all nice and smooth.
Pour the melted chocolate over the top of the Rice Crispies mixture and spread out with a spatula. Gently tap the baking tin on the counter to make sure the chocolate has spread evenly.
Leave to set again. It’ll be quicker in the fridge but will set just in your kitchen as long as it’s not too warm.
If you do chill it in the fridge, remove it half an hour or so before you want to cut it. Using a sharp knife cut it into squares to serve.
Serve and enjoy.
Mars bar slice
Ingredients
Method
- Measure the butter and golden syrup out and add to a small pan. Chop the Mars bars up and then add them to the butter.
- Melt on a low heat, stirring occasionally until it comes together in a smooth chocolate mixture.
- Meanwhile measure the Rice Crispies out into a large mixing bowl.
- Mix everything together so the Crispies are all nicely coated with the melted mars bar.
- Pour into the baking tin and press down with the back of a spoon. We found a metal spoon worked best for this as the mixture didn’t stick to it.
- Leave for 30 minutes or longer to set.
- Melt the chocolate in the microwave at short intervals, stirring to make sure it melts evenly. If you don’t have a microwave, put it in a metal bowl over a pan of simmering water to melt.
- Pour the melted chocolate over the top of the Rice Crispies mixture and spread out with a spatula. Gently tap the baking tin on the counter to make sure the chocolate has spread evenly.
- Leave to set again, before cutting into squares to serve.
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Oh my, I used to love these as a kid – my friends scottish Granny always made them for us. Pinned!
Thanks for taking me back to a happy place! And for linking to #coolmumclub
You’re welcome. I’d forgotten all about them, but glad I’ve rediscovered them!
I have never had these!! I’m so buying the ingredients after work tomorrow, L will love making them with me and eating them. Yum #coolmumclub
My other half says they were the nicest thing I’ve ever baked! They’re not exactly fine dinning but obviously must taste good!
I love these Helen. They’re so nostalgic – I think I just about remember making them but, like you, I definitely remember eating them 😉 Thankyou too for linking up with #BakingCrumbs.
Angela x
Thanks. They tasted just as good as I remembered! I need to find some more 1980/90s retro food to bring resurrect!