Baileys Mars Bar Slice

Here, I've taken the Mars Bar Slice we all know and love and added a dash of another sentimental favourite, Baileys Irish Cream. Good idea? Absolutely! Baileys Mars Bar Slice is as lovely as you'd expect.

Jump to:

• The recipe
• Ingredient notes
• How to make Baileys Mars Bar Slice
• Setting and storage
• Want more Baileys recipes?
• Baileys Mars Bar Slice Recipe

The recipe

I'm not a huge fan of messing with the classics. Pavlova is perfect just as my nan made it, old school Honey Joys can't be improved and don't dare vary Weetbix Slice. I thought Mars Bar slice was in this same category... until now.

Looking for the classic version? Try my original Mars Bar Slice recipe.

I was making up some Baileys Truffles and the smooth and chocolate-y mixture reminded me of Mars Bar Slice mixture (before the rice bubbles are added). Hmmm... I wonder if I could somehow fuse the recipes? Yes, I could. I did. And it worked a treat.

I sampled a couple of pieces and decided to freeze the rest for Christmas. But I've been sneaking to the freezer every night to extract just one little tiny square to have with my cuppa. At this rate, it'll be gone by Christmas. But that's ok because I've recorded the recipe and am sharing it here.

Ingredient notes

You'll need one of those large blocks of milk chocolate (315 grams), 3 Mars Bars, butter, golden syrup (or honey/maple syrup/corn syrup), rice bubbles (you might call them rice krispies or rice puffs) and – of course – a splash of Baileys.

I've also used a little white chocolate and green food colouring to drizzle on the topping. It helps to distinguish this as Baileys Mars Bar Slice, but is entirely optional.

See the recipe card at the end of this post for ingredient quantities and full method.

How to make Baileys Mars Bar Slice

Start by greasing a slice tin (around 27 x 17cm) with butter and then lining with baking paper.

TIP: Leave a little extra baking paper overhanging at the sides (to pull the slice from the tin once cooked).

Divide the milk chocolate into two parts - one weighing 75 grams and the other weighing 240 grams.

Next add these ingredients to a large saucepan: the mars bars (broken up with your hands), 75 gram measure of the milk chocolate, butter, golden syrup and Baileys (see image 1). Place the saucepan over very low heat and stir with a small whisk to combine (see image 2). Keep stirring until the mixture reaches a smooth, runny consistency. The mixture should resemble melted chocolate, with no lumps (see image 3).

Take off heat and add rice bubbles to the saucepan, stirring to combine well (see images 4 and 5).

Pour the mixture into your prepared slice tin.

TIP: Make sure you spread it evenly to the edges and press into the tin firmly with the back of a metal spoon (see image 6).

Now it's time to add the topping. Melt the remaining milk chocolate in the microwave using 20 second bursts (checking and stirring after each burst). Pour the melted chocolate over the slice (see image 7).

TIP: Angle the tin from edge to edge to help chocolate reach each side and corner of the slice tin.

OPTIONAL: Melt the white chocolate and add enough green powdered food colouring for a pale green colour. Drizzle over the top of your milk chocolate layer (see image 8).

Setting and storage

Place the slice into the fridge for at least 2 hours to set.

Remove the slice from tin by lifting edges of baking paper, cut into squares and return to the fridge. It will last a couple of weeks stored in an airtight container in the fridge.

TIP: Leave slice at room temperature for 15 minutes to avoid cracking the topping as you cut up your slice.

Your slice should be okay for a month or two in the freezer if wrapped or placed in an airtight container. Remove from the freezer and allow to defrost before consuming.

Want more Baileys recipes?

If you're a fan of Baileys Irish Cream, try one of these other recipes:

Made this recipe and love it? Please take a moment to rate the recipe and leave a comment below. It’s such a help to others who want to try the recipe. (And it really makes my day to hear how Nana Ling's recipes are being made, shared and loved all around the world! - Libby x)

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