Chocolate Marshmallow Tray Bake

1. 1. Preheat your oven to 180C / fan 160C / gas mark 4.

2. Put the butter, sugar and 250ml of water into a pan and gently heat until melted.

3. Take the mixture off the heat, add the flour, cocoa powder, baking powder, egg and sour cream and mix into a smooth batter before stirring in the marshmallows.

4. Pour into a lined 20cm x 30cm baking tray and cook for 25-30 minutes. To test if cooked, insert a cocktail stick – it should come out clean with no sticky bits.

5. Cool in a tray then lift out

For the frosting

1. Gently melt the butter, cocoa powder and chocolate, then add the sour cream and icing sugar and stir until smooth.

2. Cool completely – you can pop it in the fridge or place over a bowl of cold water to speed things up.

3. Beat with an electric beater until pale and lightly spreadable. Don’t worry if it separates, it will come together when fully beaten.

4. Spread over the cake and decorate with marshmallows, hundreds and thousands, little sparklers or whatever takes your fancy.