S'mores traybake

Instructions

1. Preheat the oven to 190°C, fan 170°C, gas mark 5. Grease and line a 20cm square baking tin with baking paper.
2. In a food processor, blitz the bananas then mix with the vanilla paste, vinegar, buttermilk and maple syrup.
3. In a large bowl place the flour, cocoa powder, bicarbonate soda, baking powder and salt and mix together.
4. Pour the banana mixture into the flour mixture and mix together using an electric whisk or a wooden spoon.
5. Pour the cake mixture into the prepared pan and bake for 20-25 minutes. Test the sponge by pressing the centre with your finger, if it springs back, then it is cooked.
6. Leave the sponge to cool on a cooling rack.
7. For the meringue, place the egg whites and caster sugar in a small bowl and place over a gently simmering pan of water. Making sure the bowl does not touch the water.
8. Whisk the egg whites continuously for 4-5 minutes, until the sugar has dissolved. You can test this by rubbing some of the mixture between your fingers until you can not feel the gains of sugar.
9. Remove the bowl from the pan and place the egg whites into a clean bowl. Whisk until you have a glossy meringue with stiff peaks.
10. Once the cake has cooled, place the meringue in a piping bag and pipe rows of peaks across the cake. Scorch the meringue with a blow torch or place under the grill until slightly browned.
11. Sprinkle the crushed digestives over the top and cut into 16 pieces.