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    Home » Recipes » Bars Brownies & Slices

    Mars Bar Slice

    Modified: Jun 30, 2025 · Published: Sep 14, 2020 by Lucy · This post may contain affiliate links · 60 Comments

    Jump to Recipe
    A plate of Mars Bar Slice

    Mars Bar Slice is one of those classic Aussie treats everyone remembers from childhood – rich, chewy, chocolatey, and so easy to make. With just 5 ingredients and 10 minutes prep, this no-bake slice is perfect for parties, lunchboxes, or a sneaky treat with your cuppa.

    Love old-school favourites? Try my Chocolate Coconut Slice or No-Bake Hedgehog Slice too!

    Pieces of Mars Bar Slice stacked together.

    I made the Mars Bar Slice (doubled the recipe) for all the boys at work. OMG!!!! It was gone in seconds! Thank you.

    - Nerida

    There’s something about melted Mars Bars, butter and golden syrup mixed through crispy rice bubbles and topped with a thick layer of milk chocolate… it’s the perfect combo of chewy, crunchy, and chocolatey. Sweet but not over-the-top, and incredibly simple to make – this slice is a total favourite in our house.

    And with both Thermomix and conventional methods included, you can whip it up whichever way suits you best.

    If you’re into quick no-bake slices like this, you’ll love my Clinkers Slice, Caramel Hedgehog Slice or Caramello Slice too!

    Why You're Going To Love This Recipe

    ✔️ Just 5 ingredients and 10 minutes prep
    ✔️ No oven required – simply melt, mix, and chill
    ✔️ Includes Thermomix and stovetop instructions
    ✔️ Kid-approved for lunchboxes and birthday parties
    ✔️ Freezer-friendly for make-ahead treats

    Jump to:
    • Why You're Going To Love This Recipe
    • Slice Ingredients
    • Variations
    • How To Make Mars Bar Slice
    • Top Tip
    • Recipe Tips
    • Mars Bar Slice FAQs
    • More No-Bake Slices You'll Love
    • Mars Bar Slice

    Slice Ingredients

    Note: Scroll to the recipe card at the bottom for the ingredients quantities and full detailed method.

    You only need a handful of simple ingredients – here are the key ones to get right:

    • Mars Bars – Stick with the original for that signature flavour and chewy texture.
    • Golden Syrup – Gives the slice its rich, sticky sweetness (see substitutions below).
    • Rice Bubbles – Use a fresh box so the slice stays light and crunchy.
    The ingredients for Mars Bar Slice.

    Variations

    Love a twist on a classic? Try one of these easy Mars Bar Slice variations:

    • Extra Caramel Kick: Drizzle over a little caramel sauce before adding the melted chocolate layer.
    • Gluten-Free: Use gluten-free puffed rice and double-check all your chocolate is GF.
    • Dark Chocolate Topping: Swap the milk chocolate for dark if you like it less sweet.
    • Rocky Road Style: Mix through mini marshmallows and crushed nuts before pressing into the tin.

    How To Make Mars Bar Slice

    This slice is so easy – just melt, mix, chill… and devour!

    Note: Scroll to the recipe card at the bottom for the ingredients quantities and full detailed method.

    Melted Mars Bars, butter and golden syrup in a white bowl.
    1. Step 1: Melt the base
      In a saucepan (or microwave-safe bowl), melt the butter, ⅔ of the chopped Mars Bars and golden syrup over low heat. Stir until smooth – don’t worry if some Mars Bar chunks remain.
    Sticky chocolate, caramel and rice bubble mixture in a white bowl.
    1. Step 2: Mix it up
      Add the rice bubbles and the remaining Mars Bar chunks. Mix until well coated.
    Chocolate rice bubble slice mixture pressed into a baking paper lined rectangular tin.
    1. Step 3: Press into tin
      Spoon into the tin and press the mixture down VERY firmly – this helps it hold together once set.
    Melted milk chocolate being poured on top of a chocolate rice bubble base.
    1. Step 4: Melt chocolate
      In the microwave or over a double boiler, melt the milk chocolate with the coconut oil (if using), stirring until silky smooth.
    Melted chocolate spread over a no-bake chocolate, caramel and rice bubble slice in a baking tin.
    1. Step 5: Pour & chill
      Spread the chocolate evenly over the base and chill in the fridge for at least 3–4 hours (overnight is ideal!).

    Top Tip

    Remove the slice from the fridge 30 minutes before cutting. Use a warm serrated knife to slice the Mars Bar Slice cleanly without cracking the chocolate layer!

    Recipe Tips

    • Use fresh rice bubbles so the slice stays crunchy and doesn’t go soggy.
    • No golden syrup? Swap it for honey or maple syrup in a pinch – just know it’ll have a slightly different flavour and may be a little less chewy.
    • Don't over-melt the Mars Bars – it’s fine if a few chunks remain.
    • Press the mixture firmly into the tin – use the back of a spoon or even a glass to compact it.
    • Coconut oil or vegetable oil helps prevent the chocolate layer from cracking when sliced.
    • Let it set properly – chill for at least 3-4 hours, but overnight is best.
    • Bring to room temp before slicing – this helps the chocolate soften just enough.
    • Store in the fridge in an airtight container for up to 1 week.
    Chocolate rice bubble Mars Bar Slice pieces with melted chocolate on top.

    Mars Bar Slice FAQs

    Can you freeze Mars Bar Slice?

    Yes! Wrap individual pieces and freeze in an airtight container for up to 1 month. Perfect for lunchbox fillers or last-minute guests.

    Why didn’t my Mars Bars melt properly?

    That’s totally normal! Mars Bars have nougat which doesn’t completely melt – you’ll get a gooey, sticky mix with some chewy bits, and that’s what you want.

    Do I need to use coconut oil in the chocolate?

    It’s optional but helps keep the chocolate layer from cracking when you slice. You can skip it if you don’t have any.

    Can I make Mars Bar Slice gluten-free?

    Absolutely! Just use gluten-free puffed rice and check your Mars Bars and chocolate are certified GF.

    Can I replace the golden syrup in Mars Bar Slice?

    Yes! If you don’t have golden syrup, you can substitute it with corn syrup, honey, or maple syrup. Keep in mind, golden syrup gives the slice its classic caramel flavour and stickiness, so other options may slightly change the taste and texture.

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      Peppermint Chocolate Slice | New & Improved Recipe
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      Lemon Coconut Slice - New & Improved

    WANT EVEN MORE DELICIOUS RECIPES? Subscribe to my newsletter or follow along on Facebook or Instagram. And if you love baking, then please come and join my Facebook cooking club group or subscribe to my YouTube channel. 

    Pieces of Mars Bar slice with chocolate on top stacked together.

    Mars Bar Slice

    Everyone's favourite no-bake Mars Bar Slice recipe couldn't be easier to make... with just 5 ingredients and 10 minutes prep time.
    5 from 73 votes
    Print Pin Rate
    Course: bars and slices
    Cuisine: American, australian, Australian recipe, western
    Prep Time: 10 minutes minutes
    Chilling time: 4 hours hours
    Total Time: 4 hours hours 10 minutes minutes
    Servings: 20 serves
    Calories: 151kcal
    Author: Lucy - Bake Play Smile

    Ingredients

    • 75 g (⅓ cup) butter
    • 150 g Mars Bars chopped
    • 1 tbs (20g) golden syrup
    • 3 cups (90g) rice bubbles or any puffed rice
    • 250 g (1 ⅔ cups) milk chocolate
    • 1 tbs (20g) coconut oil or vegetable oil (optional)

    Instructions

    Conventional Method

    • Grease and line a 18cm X 22cm rectangular slice tin with baking paper and set aside. 
    • Melt the butter, 100g (two thirds) of the Mars Bars and golden syrup on low heat in a saucepan (or in 30 second bursts in the microwave on 50% power). Please note: the Mars Bars will not completely melt. Mix until the butter and golden syrup are smooth.
    • Stir through the rice bubbles and the remaining Mars Bar (chopped).
    • Press mixture very firmly into the prepared tin. 
    • Place milk chocolate and coconut oil/vegetable oil in a heatproof bowl. Microwave on medium for 3 minutes, 50% power, or until just melted, stirring every 30 seconds with a metal spoon. Stir until smooth.
    • Spread over slice and refrigerate until firm (a minimum of 3-4 hours - or best overnight).
    • Remove slice from the refrigerator about 30 minutes before cutting into squares with a warm serrated knife.

    Thermomix Method

    • Grease and line a 18cm X 22cm rectangular slice tin with baking paper and set aside. 
    • Place 100g (two thirds) of the chopped Mars Bars, butter and golden syrup into the Thermomix bowl. Melt on 60 degrees, Speed 2 for 3 minutes.
    • Add the rice bubbles and the remaining Mars Bar. Mix on Reverse, Speed 2, 15 seconds or until completely combined.
    • Press the mixture very firmly into the prepared tin.
    • Place the milk chocolate into a clean TM bowl. Melt on 50 degrees, Speed 3 for 2-3 minutes (scraping down the sides of the bowl occasionally).
    • Spread over slice and refrigerate until firm (a minimum of 3-4 hours - or best overnight).
    • Remove slice from the refrigerator about 30 minutes before cutting into squares with a warm serrated knife.

    Notes

    Recipe Notes & Tips
    • Use fresh rice bubbles so the slice stays crunchy and doesn’t go soggy.
    • No golden syrup? Swap it for honey or maple syrup in a pinch – just know it’ll have a slightly different flavour and may be a little less chewy.
    • Don't over-melt the Mars Bars – it’s fine if a few chunks remain.
    • Press the mixture firmly into the tin – use the back of a spoon or even a glass to compact it.
    • Coconut oil or vegetable oil helps prevent the chocolate layer from cracking when sliced.
    • Let it set properly – chill for at least 3-4 hours, but overnight is best.
    • Bring to room temp before slicing – this helps the chocolate soften just enough.
    • Store in the fridge in an airtight container for up to 1 week.

    Nutrition

    Calories: 151kcal | Carbohydrates: 15g | Protein: 1g | Fat: 11g | Saturated Fat: 7g | Cholesterol: 8mg | Sodium: 30mg | Potassium: 61mg | Fiber: 1g | Sugar: 11g | Vitamin A: 95IU | Calcium: 6mg | Iron: 0.6mg
    Did you try this recipe?Mention @BakePlaySmileBlog or tag #BakePlaySmile!

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    Comments

    1. Maria says

      June 24, 2019 at 3:14 pm

      im wondering ifi the owner ot thermobliss and bakeplaysmile are the sam, because i see that the recipe its exactly the same with the only difference the coconut oil in the chocolate

      Reply
      • Lucy Mathieson says

        June 24, 2019 at 8:22 pm

        Hi Maria, I own half of ThermoBliss with my very good friend Lauren (who also owns a website called Create Bake Make). So yes!!! I'm both here and over at ThermoBliss!!!

        Reply
    2. Alicia says

      May 13, 2019 at 2:08 pm

      Is this recipe suitable for freezing? I’d prefer not to but just wanted to check!

      Reply
      • Lucy Mathieson says

        May 27, 2019 at 4:16 pm

        Hi Alicia, yes you can freeze this recipe. xx

        Reply
    3. John Malcon says

      December 07, 2017 at 9:13 pm

      Hello, Lucy!
      Thank you for the perfect recipe! I sent to my wife a link on your blog!
      John
      Weedit.photos

      Reply
      • Lucy Mathieson says

        December 08, 2017 at 4:22 am

        Thank you!!!

        Reply
    4. Lily says

      August 26, 2017 at 2:20 pm

      Hello hello - me again - how long will it last in the fridge???

      Reply
      • Lucy Mathieson says

        August 27, 2017 at 5:03 pm

        Hi again! Up to 5 days 🙂

        Reply
    5. Tracey says

      January 03, 2017 at 8:56 pm

      Coming from the uk I was wondering if you can tell me how many grams is in a cup? Love the sound of the mars bar slice as it's one of my favourite chocolate bars
      Oh & seeing as you like Turkish Delight you might want to try these - Turkish Dekight Rocky Roads
      Ingredients

      100g butter, roughly chopped
      300g dark chocolate, broken into squares
      3 tbsp golden syrup
      140g rich tea biscuit, roughly crushed
      12 pink marshmallow, quartered (use scissors)
      2 x 55g bars Turkish delight, halved and sliced

      Method

      Gently melt the butter, chocolate and syrup in a pan over a low heat, stirring frequently until smooth, then cool for about 10 mins.
      Stir the biscuits and sweets into the pan until well mixed, then pour into a 17cm square tin lined with foil and spread the mixture to roughly level it. Chill until hard, then cut into fingers.

      Reply
      • Bake Play Smile says

        January 05, 2017 at 8:51 am

        Yum sounds delicious!! You might find this website helpful for converting ingredients: http://dish.allrecipes.com/cup-to-gram-conversions/

        Reply
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    I’m Lucy! A mum, a wife, a food blogger and a lover of all things to do with food! I love creating delicious, no-fuss Thermomix and conventional recipes the whole family will love. Classic baking favourites, lunch box snacks, quick and easy family dinners and more!

    More about me →

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