For salted caramel, place 80 g caster sugar, half the glucose and 80 ml water in a small saucepan over medium heat until the sugar has completely dissolved, then increase the heat slightly, and cook until it is a nutty caramel colour – about 15 – 20 mins. Do not stir as it can potentially crystalize. Remove from the heat and immediately add the cream and butter and stir to combine. Allow to cool a little, then stir through the Vanilla Salt – if you do this while very hot, the salt will dissolve, and it is nice to have little pops of salt in the mixture. Set aside at room temperature.
For marshmallow base, cover gelatine leaves in cold water and allow to soften for about 5 mins. In a small saucepan, over medium heat, combine the remaining caster sugar, glucose and 100 ml water to dissolve, then cook without stirring until the mix reaches 127°C on a sugar thermometer.
Place the egg whites and a pinch of salt in a stand mixer and whisk to soft peaks, then add the vanilla sugar and whisk until glossy. When the syrup has come up to temperature, squeeze out all excess liquid from the gelatine and combine with the syrup until dissolved. With mixer running on LOW speed, slowly pour the syrup into the egg whites, scraping down the sides of the bowl as necessary. Once all the syrup has been incorporated, increase the speed and allow the egg whites to whisk until the mix no longer feels warm when you touch the bowl.
Lightly oil a high-sided tray and set aside. Gently fold spoonfuls of the caramel through the mix – don’t over-mix so you have a slight ripple effect. Spoon the mixture into the tray, smoothing the top with a spatula. Transfer to the fridge and allow to set.
Sift together the icing sugar and cornflour. Once set, cut the marshmallows into squares and dust with the sugar mixture.
A sugar thermometer and a stand mixer are recommended for this recipe.
While these will keep for about a week in an airtight container, best eaten straight away.