Peppermint Slice – dairy-free

By lucylox on March 16, 2025

Are you fan of mint chocolate? Then this is the recipe for you, especially if you'd like it to be dairy-free and egg-free too!

Top of the morning to you! With St Patrick's day on the horizon, it's time to embrace the green!

I recently came across the idea of peppermint slice and it's stuck with me. I'm not so familiar with mint flavoured bakes but somehow the idea of a mint and chocolate traybake is an intriguing idea, one that I just had to give a go. With St Patrick's day fast approaching any green food is topical, so now is most certainly the time to have peppermint slice on the menu.

On deeper research, it seems like i've been missing out and peppermint slice is a traditional traybake, featuring three layers: a crunchy, crumbly cocoa heavy biscuit base, covered with a mint flavoured fondant and then topped with chocolate. More often than not Mint Aero is used to garnish the top, but as Mint Aero contains milk, it won't feature in my version. Instead I've used chopped up Nomo Mint mini bars, which i think add a rather tempting garnish and an extra minty boost to the flavour.

I've decided to colour the fondant green, making it particularly appropriate for St Patrick's Day, but I feel that leaving it white may give an even greater dramatic colour contrast. In lots of recipes I've come across the quantity of peppermint is quite surprisingly large, so I've dialled it way back with between 1/2-1 tsp depending on how much you like mint flavour. I'm more of a fan of a subtle mint flavour as I feel it makes the chocolate stand out to better effect. But do feel free to add more if you like a bigger blast of refreshing mint!

This recipe makes 8 slices in a 2lb loaf tin, which has become my most usual bake size as it means i don't make too much, but it's still plenty for a family of four. If you want to make a usual 8"square tin for 14-16 slices, then just double the recipe.

Peppermint Slice - dairy-free recipe

Chocolate biscuit base, topped with mint flavoured fondant and chocolate

2lb loaf tin
sheet of baking paper

to make the biscuit base

125 g self-raising flour
50 g caster sugar
1 tbsp cocoa powder
110 g dairy-free margarine (melted)
35 g crushed cornflakes (or chocolate cornflakes)

To make the fondant layer

250 g icing sugar
½-1 tsp peppermint essence
2 tbsp water
½ tsp green food colour (optional)

For the chocolate topping

90 g dairy-free dark chocolate
3 mini Nomo mint choc bars (roughly chopped)

Preheat the oven to 180℃ and line the loaf tin with baking paper
Sift the flour and cocoa powder into a large bowl. Stir in the sugar.
Crush the cornflakes and add to the bowl
Pour in the melted margarine and mix to form a dough
Press into the base of the lined tin and bake for 15 minutes
Leave to cool

To make the fondant layer and topping

Mix together the icing sugar, water, mint and essence and green food colour (if using)
Pour over the cooled biscuit base and level off
Melt the chocolate and pour over the fondant layer
roughly chop the mint Nomo bars and scatter over the chocolate layer
Leave to set and then cut into 8 bars