Gluten free Mars bar slice, Curly Wurly slice

Posted: August 26, 2025 Updated: August 26, 2025

Mars bar slice is an Aussie classic, but honestly I’m not sure I’ve ever had it, let alone gluten free. It’s one I see pop up on my feed though, often as a suggestion for easy party treats.

Well, I’m all about easy cooking and baking. Because honestly, I’m a bit useless in the kitchen at times. Or rather, it gets me stressed.

I stress because I worry that it won’t work. Or worse, I try a recipe from a blog I’ve never used before and it’s a disaster. So I never try again.

But with no bake recipes it’s just that little bit easier, especially Aussie-style slices. Cereal mixed with chocolate bars, biscuits mixed with condensed milk… Not too much room for things to go wrong. 😁

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Mars bars out Curly Wurly in

I’m sure more than a few of you were wondering, “But Kati, how do you make a Mars bar slice when they aren’t gluten free?”

Well, that is very true. Mars Bars in Australia use barley malt extract which is not gluten free. I thought they might be in the UK, but I’m getting mixed up with Snickers.

If you’re in Australia, Snickers used to be gluten free but now have a may contain.

Curly Wurly is what you will need to make a gluten free version of Mars bar slice. The caramel and chocolate combination create the sticky chocolate mix needed to perfectly coat and bind the rice bubbles.

You can use Curly Wurly bars or Curly Wurly Swirlies, which are mini snake like pieces of Curly Wurly. They also come in at a better price point.

Ingredients for gluten free Mars bar slice (Curly Wurly slice)

There are only four ingredients and about twenty minutes between you and a delicious slice. Here’s what you’ll need.

• 90g rice bubbles (about 3 cups)
• 60g butter
• 180g Curly Wurly (about 1.5 bags of swirlies)
• 225g chocolate buttons for the topping

Note, while many Mars bar slice recipes include golden syrup I’ve chosen to leave this out. With the golden syrup in the recipe it becomes cloyingly sweet. You’ll try one piece and not want another one.

Without it, the slice is lighter and more enjoyable – you’ll want to eat more.

Similarly I’ve reduced the volume of butter compared to other recipes, it just doesn’t need it.

For cooking chocolate without a may contain for gluten you’ll want Cadbury or Nestle melts, both found in the baking aisle. Both come in 225g bags, which is why I’ve listed 225g in the recipe.

I actually used 200g for the slice in the photos but I could have done with a smidge more.

Other than that the main thing you’ll need is a slice pan which you can pick up at Kmart for a few bucks or buy on Amazon.

Gluten free options for rice bubbles

There are a few gluten free options for rice bubbles in Australia. Here are the main three

• Freedom rice crispy rice puffs, available at Coles and Woolworths
• Kellogg’s gluten free Rice Bubbles, available at Coles, Woolworths and Amazon.
• Orgran Rice Puffs, from Happy Tummies and Amazon.

While on Happy Tummies I also came across Good Morning brown rice puffs. I’m assuming they have a similar texture to the rest and would work well in this recipe.

Method

You can see the recipe card further down the page, but if you prefer to have a few reference photos as you go, this is for you.

Start by lining a 28cm x 18cm slice tin with baking paper. A 22x22cm tin would also work.

In a small saucepan, combine butter and Curly Wurly pieces. Stir over a medium-low heat until melted and combined.

Note: While Mars bar recipes offer a microwave option I found that the higher volume of caramel in Curly Wurlys made it incredibly tedious to melt in the microwave.

Pour your rice bubbles into a large mixing bowl. Add the melted Curly Wurly butter mixture and stir until combined.

Press the mixture into your lined tin. Smooth it out and press into place using the back of a spoon. Set aside and prepare the chocolate.

Using a double boiler (a heatproof bowl over a saucepan of boiling water) melt the chocolate. If you wish you can use a microwave, heating in 30 second bursts on medium powder.

Once fully melted and smooth pour the chocolate over the slice.

To get a smooth finish on the chocolate topping gently tap the pan on the bench and watch it magically smooth out.

Refrigerate for three hours (or overnight).

Remove from the fridge, sit for 20 – 30 minutes (to aid cutting) then slice and serve.

Add ins and upgrades

Want a Snickers vibe? Add 75g chopped peanuts. You can buy unsalted peanuts without a may contain from Woolworths (blue packet).

Christmas time? Use up some of those leftover festive sprinkles on top.

Fancy a prettier finish? Heat up some white chocolate as well and marble the top together with the milk chocolate.

Tips on a smooth cut

At the end of the recipe the slice goes in the fridge to set. Chilled down, the chocolate on top can become quite brittle and is liable to snap when you go to slice it.

Instead, bring the slice out of the fridge 20 minutes before slicing. This will allow the chocolate to come to room temperature and (hopefully) slice without snapping.

Alternatively, warm your knife by running it under hot water and then drying with a clean cloth. The warmth of the knife will help it move through the slice cleanly.

I had read a tip to use a serrated / bread knife. Don’t do it, it is a disaster! 😂

Storing gluten free Mars bar slice

Mars bar slice is best kept in the fridge and will keep for about a week (if it’s not all eaten!).

Alternatively cut pieces can be stored in the freezer. This is great if you’re baking just for yourself. A frozen piece of slice defrosts quite quickly, so you only need to take it out ten minutes before eating. Or about the time it takes to make a fancy coffee.

Oh, and these slices taste quite nice when they’re a bit cold.

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