Quick Mars Bar Slice Recipe — No-Bake Chocolate Treat

If you love Mars Bars, you’ll adore this easy Mars Bar Slice. It’s a no-bake treat with a satisfying mix of crunch and chew, packed with classic Mars Bar flavour. Read on to find how simple it is to make.

Why you’ll love this recipe

My brother is a huge Mars Bar fan, and this Mars Bar Slice is one of his favourites alongside Mars Bar cupcakes. With crunchy puffed rice, pockets of caramel and nougat, and a milk chocolate topping, it delivers the familiar Mars flavour in a quick, no-bake bar.

Ingredients

Not sure what to buy or what to swap? The list below covers what I use and suggested alternatives.

• Mars Bars – Use original Mars Bars for the authentic flavour, though cheaper alternatives will still work.
• Butter – Unsalted or salted is fine; it helps melt the Mars Bars into a smooth mixture.
• Golden Syrup – Adds a subtle caramel note; don’t skip if you can help it.
• Puffed Rice Cereal – Rice Krispies are my choice, but any puffed rice cereal will do.
• Milk Chocolate – Choose a chocolate you like; Galaxy pairs especially well with Mars flavour.
• Blonde Chocolate – Optional for decoration. White chocolate or a blonde bar such as Caramac works nicely.

Emma’s top tips

Helpful pointers to get the best result:

• Melt the Mars Bars slowly over low heat. A gentle approach prevents burning; it’s okay if some nougat remains.
• Use a smooth milk chocolate like Galaxy for the topping to enhance the Mars Bar flavour.
• If you need the bars quickly, chill them in the fridge, but expect the chocolate to lose some snap from the rapid temperature change.

Timings

A quick breakdown to help plan your time:

• Melting Mars Bars: 5–10 minutes.
• Mixing with rice cereal: under 5 minutes.
• Pressing into the tin: about 3 minutes.
• Melting and smoothing chocolate topping: around 5 minutes.
• Optional decoration: 2–3 minutes.

Mars Bar Slice – Step by step

(Printer-friendly recipe card at the end)

Ingredients

Makes 9 large bars or 16 smaller bars. Includes UK metric and US cup measurements.

• 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 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 small plastic bag (optional), skewer or knife (optional)

Instructions

Lightly grease and line the tin so the paper will stick. Roughly chop two and a half Mars Bars and place them in a small saucepan. Chop the remaining one and a half into small pieces and set aside.

Add the butter and golden syrup to the saucepan and melt over low heat, stirring constantly. Remove from heat and allow to cool slightly; it’s fine if some nougat remains.

Tip the Rice Krispies and the reserved chopped Mars Bar pieces into a large bowl. Pour the melted mixture over and stir until the cereal is well coated.

Press the mixture firmly into the lined tin and chill in the fridge while you prepare the topping.

Break the milk chocolate into a heatproof bowl and melt in 10 second bursts in the microwave, stirring between intervals. When mostly melted, remove and stir until smooth. Pour and smooth over the chilled base.

Optional decoration

Note: work quickly — if the milk chocolate begins to set the feathering effect won’t work.

Break the blonde chocolate into a small bag, microwave in 10 second bursts and squeeze to combine until melted. Snip a tiny corner and pipe thin lines across the milk chocolate, then drag a skewer perpendicular to the lines to create a feathered pattern. Allow to set at room temperature.

How to slice and store Mars Bar Slice

The bars can be sticky — warm a sharp knife under hot water, dry it, and slice. Cut into 9 or 16 pieces. Store in an airtight container in the fridge and eat within five days.

FAQs

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Easy Mars Bar Slice Recipe

Yield:
16

Prep Time:
20 minutes

Total Time:
20 minutes

Love Mars Bars? This no-bake Mars Bar Slice combines crunchy rice cereal and gooey Mars Bar pieces under a smooth milk chocolate layer.

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 x Large Mixing Bowls
• Spatula
• Piping Bag (or plastic food bag), optional
• Skewer (or knife), optional

Instructions

1. Lightly grease and line the baking tin. Roughly chop 2½ Mars Bars and place in a saucepan with the butter and golden syrup. Chop the remaining 1½ Mars Bars and set aside. Melt gently over low heat, stirring constantly, then set aside to cool.
2. Put the Rice Krispies and reserved chopped Mars Bars into a mixing bowl. Add the melted mixture and stir until evenly coated.
3. Press the mixture into the lined tin and chill in the fridge.
4. Break the milk chocolate into a bowl and melt in the microwave in 10 second intervals, stirring between. When mostly melted, remove and stir until smooth. Pour over the chilled base and smooth with a spatula.

Optional Decoration

NOTE You need to act quickly; if the milk chocolate begins to set the feathering effect won’t work.

1. Break the blonde chocolate into a piping bag and microwave in 10 second bursts, squeezing after each to combine, until fully melted.
2. Snip a small corner and pipe lines across the milk chocolate topping.
3. Drag a skewer perpendicular to the piped lines to create a feathered pattern. Allow to set at room temperature before slicing.

Notes

If you need more guidance, the full post includes extra tips and FAQs. This recipe shows both UK metric and US cup measurements.

Slicing and storage

Warm a sharp knife under hot water, dry it, then slice into 9 or 16 pieces. Store in an airtight container in the fridge and consume within five days.

Tips

• Melt Mars Bars gently to avoid burning.
• Use a smooth milk chocolate like Galaxy for the topping if possible.
• If you chill quickly, the chocolate may lose some snap.

Recommended Products

As an Amazon Associate and member of other affiliate programs, I earn from qualifying purchases at no extra cost to you.

• 
  Lyle’s Golden Syrup Baking Bottle, 600g
• 
  Pyrex Glass Mixing Bowl Set 3 Piece

Nutrition Information:

Yield: 16
Serving Size: 1

Amount Per Serving:
Calories: 177Total Fat: 10gSaturated Fat: 6.5gTrans Fat: 0gUnsaturated Fat: 3.2gCholesterol: 18mgSodium: 16mgCarbohydrates: 19gFiber: 0.8gSugar: 13gProtein: 1.8g

Did you make this recipe?

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If you like this Mars Bar Slice recipe…

…you might also enjoy:

• Malteser tiffin bars
• Kinder Bueno brownies
• Mars Bar cookies
• Air fryer Creme Egg croissants
• Easy Twix brownies

I want to see YOUR baking!

Have you tried this Mars Bar Slice? I’d love to see your photos. Tag me on social media or email me at [email protected].