If you love Mars Bars, you’ll adore this easy Mars Bar Slice. It’s a no-bake treat that combines a crunchy, chewy base with pockets of caramel and nougat, all finished with a silky milk chocolate topping. Read on to see how simple it is to make.
Why you’ll love this recipe
This Mars Bar Slice is one of my brother’s favourites — and it’s easy to see why. Crispy puffed rice gives it crunch, while chopped Mars Bars create caramel and nougat pockets. A milk chocolate layer on top finishes it off for a truly indulgent no-bake treat.
Ingredients
Below are the ingredients and easy substitutions to help you choose what to buy.
- Mars Bars – Using the original Mars Bars gives the best flavour, though budget alternatives will still work.
- Butter – Unsalted or salted is fine; it helps melt the Mars Bars evenly.
- Golden Syrup – Adds a deeper caramel note; don’t skip if you can help it.
- Puffed Rice Cereal – Rice Krispies or any puffed rice brand will do.
- Milk Chocolate – Use a chocolate you like; Galaxy is a good match for Mars Bar flavour.
- Blonde or white chocolate – Optional for decoration, but it gives a lovely contrast.
Emma’s top tips
Helpful tips for the best result:
- Melt the Mars Bars gently over low heat to avoid burning. It’s okay if the nougat doesn’t fully dissolve.
- For an authentic flavour, use Galaxy or another smooth milk chocolate for the topping.
- If short on time, chill in the fridge to set, but be aware the chocolate may lose some of its snap when chilled quickly.
Timings
Quick overview of how long each stage takes:
- Melting Mars Bars: 5–10 minutes
- Mixing with rice cereal: under 5 minutes
- Pressing into the tin: about 3 minutes
- Melting and spreading chocolate: about 5 minutes
- Optional decoration: 2–3 minutes
Mars Bar Slice – Step by step
(Printer-friendly recipe card appears at the end of this post.)
Ingredients (makes 9 large or 16 smaller bars)
Measurements include UK metric and US cup equivalents.
- 4 x 39g (1.4 oz) Mars Bars
- 75g (1/3 cup) unsalted butter
- 1 tsp golden syrup
- 75g (about 3 cups) Rice Krispies
- 200g (7 oz) milk chocolate
- 60g (2.1 oz) blonde or white chocolate (optional)
Essential equipment
- 20cm (8″) square baking tin
- Chopping board and sharp knife
- Saucepan and wooden spoon
- Large mixing bowls, spatula
- Piping bag or plastic bag (optional), skewer (optional)
Instructions
1. Lightly grease and line the baking tin with baking paper.
2. Roughly chop 2½ Mars Bars and put them in a small saucepan with the butter and golden syrup. Chop the remaining 1½ Mars Bars into small pieces and set aside.
3. Warm the saucepan over low heat, stirring constantly until the mixture is melted and combined. Remove from heat and allow to cool for a few minutes.
4. Place the Rice Krispies and the reserved chopped Mars Bar pieces into a large bowl. Pour the melted mixture over and stir thoroughly to coat.
5. Press the mixture firmly into the lined tin and chill in the fridge while you melt the chocolate for the topping.
6. Break the milk chocolate into a heatproof bowl and microwave in 10-second bursts, stirring between each burst. Stop when about two-thirds melted, then stir until smooth.
7. Pour and spread the melted milk chocolate evenly over the chilled base with a spatula.
Optional decoration
Note: Work quickly — feathering won’t work if the milk chocolate has set.
8. If using blonde or white chocolate, place it in a piping bag or small food bag and microwave in 10-second bursts until melted, squeezing the bag between bursts to combine.
9. Snip the tip and pipe lines across the chocolate, then use a skewer to drag lines perpendicular to them to create a feathered effect. Allow to set at room temperature.
How to slice and store Mars Bar Slice
Cut with a warm, clean knife to reduce stickiness: run a sharp knife under hot water, dry it, then slice into 9 or 16 pieces. Store in an airtight container in the fridge and use within five days.
FAQs
Yes. Melt them gently over low heat; the nougat may not fully melt, but that’s fine for this recipe.
No. Any puffed rice cereal works, so use whatever’s available or on offer.
Printable recipe card
Easy Mars Bar Slice Recipe
Love Mars Bars? This no-bake slice gives you that classic flavour in an easy, crunchy, chewy bar.
Ingredients
- 4 x 39g (1.4 oz) Mars Bars
- 75g (1/3 cup) unsalted butter
- 1 tsp golden syrup
- 75g (3 cups) Rice Krispies
- 200g (7 oz) milk chocolate
- 60g (2.1 oz) blonde chocolate, optional
Essential Equipment
- 20cm (8″) square baking tin
- Chopping board, sharp knife
- Saucepan, wooden spoon
- 2 large mixing bowls, spatula
- Piping bag (optional), skewer (optional)
Instructions
- Lightly grease and line the tin. Roughly chop 2½ Mars Bars and place in a saucepan with butter and golden syrup. Chop the remaining 1½ Mars Bars and set aside. Melt gently over low heat, stirring. Set aside to cool.
- Mix the Rice Krispies with the reserved chopped Mars Bar pieces in a large bowl. Pour the melted mixture over and stir to combine.
- Press into the prepared tin and chill in the fridge.
- Melt the milk chocolate in a bowl in 10-second bursts, stirring until smooth. Pour over the chilled base and smooth out.
- Optional: melt blonde chocolate in a piping bag, pipe lines across the top, then feather with a skewer. Allow to set before slicing.
Notes
Slicing and storage: use a warm knife for clean cuts. Store in an airtight container in the fridge and eat within five days.
Tips
- Melt Mars Bars slowly to avoid burning.
- Use a smooth milk chocolate for the topping for best flavour.
- Chilling speeds set time but may reduce chocolate snap.
Nutrition Information:
Yield: 16
Amount Per Serving:
Calories: 177
Total Fat: 10g
If you like this Mars Bar Slice recipe…
…you might also enjoy other easy no-bake and chocolate bar inspired treats.
- Malteser tiffin bars
- Kinder Bueno brownies
- Mars Bar cookies
- Air fryer Creme Egg croissants
- Easy Twix brownies
I want to see YOUR baking!
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