Burger cake

Method

Make the sponge ‘buns’:

1. Preheat the oven to 180°C/fan 160°C fan/gas 4
2. Grease and line 2 x 20cm sandwich tins
3. Beat together the butter and caster sugar until light and fluffy, then beat in the eggs one at a time
4. Once the eggs are fully incorporated, add the vanilla extract, then beat in the flour
5. Divide between the prepared tins and bake for 20-25 mins, until golden, risen and a skewer inserted comes out clean
6. Leave to cool in the tin for a few minutes before turning out onto a wire rack to cool completely

Make the brownie 'patty':

1. Grease and line the base and sides of a 20cm sandwich tin
2. Melt together the butter and chocolate in a small saucepan over a very low heat, stirring all the time, until melted
3. Remove from the heat and set aside
4. In a mixing bowl, beat together the eggs and caster sugar for around 5 mins, until the mixture is light and the whisks leave a trail when lifted
5. Gently pour the chocolate mixture into the whisked eggs and fold in, then add the flour and cocoa
6. Pour into the prepared tin and bake for 20-25 mins
7. Then leave to cool in the tin

Prepare the buttercream and decorations:

1. To make the buttercream, beat the butter in a stand mixer until pale (around 3 mins), then add half the icing sugar and beat in fully, before adding the rest
2. Continue beating for another 2-3 mins, until the buttercream is almost white
3. Beat in the milk and vanilla, then remove 1/3 of the buttercream and place in a separate bowl
4. Mix the cocoa into the smaller amount of buttercream, until it is a light brown colour, then beat a few drops of the green gel colour into the larger amount
5. Spoon the green buttercream into a piping bag fitted with a flat nozzle
6. Colour the fondant icing with the yellow gel food colouring until it resembles 'cheese'
7. Sprinkle a work surface with icing sugar and roll out the fondant to a square with edges just longer than 20cm (use a ruler to keep the edges straight)
8. Put the jam into a piping bag fitted with a small round nozzle, or into a disposable bag with the end snipped off

To assemble:

1. Choose the most rounded of the two sponges to use as the top burger bun
2. Trim the edges with a serrated knife to make the top even more rounded
3. Spread a very thin layer of the brown buttercream over this sponge, then chill in the fridge for about 30 mins
4. Put the other sponge on a serving plate to use as the base, and spread the sides with a little of the brown buttercream
5. Pipe the green buttercream in ruffles all around the edge on top of the base sponge, then fill in the middle with the remaining buttercream
6. Top this layer with the brownie
7. Drape the yellow fondant cheese over the brownie, then squirt over the jam to look like ketchup
8. Take the top sponge out of the fridge and spread over the rest of the brown buttercream
9. Place on top of the jam and fondant layer, then dust the top with a little extra cocoa and scatter over the white chocolate sprinkles to serve
10. Keep the cake cool if you’re not serving it straight away