Gluten Free Marshmallow Slice

Marshmallow slice, need I say more?

This two-layer slice consists of a thick and fluffy marshmallow layer with a rich buttery cake layer. Each bite feels like you are biting into a slice of baking heaven, which will have you going back for seconds if not thirds.

No amount of words could do this slice justice, there is just something about the whipped marshmallow layer combined with the fluffy shortcake base that is all sorts of incredible. 

All the ingredients you will need.

Growing up this use to be one of my favourite slices, I was obsessed with marshmallow tarts, marshmallow slice and marshmallow ice cream cones. 

The finished base mixture should look like this.

It wasn’t until I went back to New Zealand on holiday recently that I was reminded just how good marshmallow slice was, I’m not sure if its just a New Zealand thing but I haven’t seen any marshmallow slices here in Melbourne? After seeing multiple cafes in Wellington selling a non gluten free version of the slice, I was determined to recreate a gluten free version when I was home. 

Make sure you smooth out the top of your base so it cooks evenly.

I can happily report that not only was this recipe a huge success first round (a big deal when it comes to gluten free baking) but it was approved by my family members who both said it was just as good as the version that contained gluten. 

Your marshmallow mixture is ready when it starts to form stiff peaks like this.

When it comes to marshmallow slice there are a range of variations, some marshmallow slices are white opposed to pink, some have a thin layer of jam (strawberry or raspberry) in-between the marshmallow and cake base, some have a thin layer of chocolate on top of the marshmallow and if you are a coconut lover, you can sprinkle some toasted desiccated coconut on top of the marshmallow layer. Regardless of whether you choose to add some extra toppings or stick with the traditional marshmallow and cake base, this slice won’t disappoint. 

My biggest tips for this recipe would be when it comes to the marshmallow make sure you add your gelatine mixture to your icing sugar and egg yolk slowly, you don’t want to add it all at once as it will melt the icing sugar and cause it not to thicken properly. 

Secondly don’t stress if you feel like your marshmallow isn’t thickening up, when I was testing this recipe I didn’t think my marshmallow would thicken, but I can assure you it does. You just need to be patient when it comes to the mixing process, it will take time and you will need to use an electric mixer/beater opposed to a standard whisk. 

If you get the chance to make this gluten free Marshmallow slice I would love to know what you think, feel free to tag me over at @itsallglutenfree on Instagram!

Gluten Free Marshmallow Slice

Prep Time30 mins
Cook Time26 mins
Total Time56 mins
Course: Baking, Dessert
Author: Its All Gluten Free


  • 125 grams Butter Softened
  • 3/4 cup (98 grams) Icing Sugar
  • 1 Egg
  • 1 teaspoon Vanilla Essence
  • 1 1/4 cups (165 grams) Gluten Free Self Raising Flour


  • 1 cup Cold Water
  • 2-3 drops Pink Food Colouring
  • 1 tablespoon Gelatine Powder
  • 1 cup (235 grams) Caster Sugar
  • 1 Egg white
  • 1 cup (140grams) Icing Sugar
  • Electric mixer


  • Preheat your oven to 160 degrees (fan forced) and line your chosen slice tray with baking paper. 
  • Beat your butter and icing sugar together with an electric mixer until smooth in texture. Then add in your egg and vanilla essence and mix until combined. 
  • Slowly add your flour to your wet mixture, making sure to mix in between each addition. 
  • When your mixture is combined pour it into your lined baking tin and bake for 25-27 minutes. Your base should be golden brown in colour and clean when a skewer is inserted (Depending on what slice tin you use it may take longer/less time to cook)
  • Once the base is cooked remove it from the oven and allow too cool in the tin. Whilst your base is cooling begin to make your topping.
  • To make your marshmallow layer, place the cold water in a medium size saucepan on a medium heat. 
  • Add a few drops of your pink food colouring (I only used two drops, as you can always add more later on) then sprinkle in your caster sugar and stir with a whisk for a minute. Then sprinkle in your gelatine powder over the top (if you sprinkle it, its less likely to go lumpy)
  • Stir continuously until the sugar and gelatine powder has dissolved into the water. Then boil your mixture for on a medium heat for 9 minutes, stirring occasionally. 
  • While your liquid is boiling, use a separate bowl to whip your egg white until it forms soft peaks. 
  • Once your mixture has been boiling for 9 minutes, remove from the heat and allow to cool slightly. 
  • Now slowly beat in your icing sugar into your egg yolk, once combined slowly pour in your warm gelatine mixture (You want to add this slowly and mix between each addition)
  • Once all of your gelatine mixture has been added, continue to mix with the electric mixer. This can take anywhere from 10 minutes to 25 minutes. You will know your marshmallow is ready when it forms stiff peaks, see picture above for reference. 
  • Make sure the sides of your baking tin are covered with baking paper so that the marshmallow wont stick to the sides of your tin.
  • When your marshmallow is a thick and fluffy consistency, gently spread it over the top of your cake base, making sure to evenly spread the marshmallow and tap to avoid air bubbles. Once the marshmallow layer has been spread, allow to cool for 2-3 hours, then slice and enjoy!


*The brand of flour I use is Orgran as it is my personal favourite. I have not tried this recipe with any gluten free flour other than Orgran.

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