Step 1

You need to work quickly making this so have a prepared large flat baking tray ready to set the popcorn and all the ingredients to hand.

Step 2

Add the sugar and water to a large pot on a medium-low heat. Don't stir but you can shake to stop it burning.

Step 3

Once the sugar turns a deep caramel colour, remove from the heat and add the tablespoon of dairy-free butter. It will bubble up, keep stirring until smooth.

Step 4

Then pour over the bowl of popped corn. Quickly transfer to the tray to set.

Step 5

Preheat the oven to 180C / 350F and grease and line two 8-inch cake tins.

Step 6

Mix the wet ingredients together in a jug or medium bowl. Mix all the dry ingredients into a large bowl, and the whisk together until well combined. The vinegar will react with the rising agents so don't let it sit too long.

Step 7

Pour the batter equally between the two cake tins and bake for approximately 35 minutes or until a toothpick poked into the middle of the cake comes out clean.

Step 8

Once baked, leave to cool completely before removing from the tins. Then freeze the two layers for a few hours, so it's easier to trim.

Step 9

Remove from the freezer and trim the tops to make them even. Now slice each layer in half, length-ways, to create four cake layers.

Step 10

Follow instructions from my "5 Minute Caramel Sauce" recipe. Allow it to cool before using, but note it will harden if chilled too much.

Step 11

Whisk the dairy-free butter in a large mixing bowl, adding the icing sugar a small bit at a time.

Step 12

Then whisk in the caramel sauce, working whilst the sauce is room temperature and at a pourable consistency to stop it from hardening.

Step 13

Let the buttercream chill in the fridge for at least a couple of hours before using.

Step 14

Add buttercream to the top of the first cake layer and sandwich together with the next layer, repeating and covering all layers with a generous dollop of the buttercream.

Step 15

Then frost the outside of the cake, starting with a thin crumb layer before adding a more generous coating.

Step 16

When the caramel sauce has cooled but is still a thick, pourable consistency, pour over the top of the cake, letting it run down the sides.

Step 17

Pile the popcorn on top and pour more caramel over to keep it in place.

Step 18

Leave in the fridge for a few hours to set and keep fresh, before serving.