Brooklyn blackout cake

Cuts into 12 Prep 30 mins plus cooling and chilling Cook 30- 40 mins

140g unsalted butter, plus extra for the tins

100ml vegetable oil

140g buttermilk

100ml coffee, made with

1 tsp espresso powder

2 large eggs, at room temperature

1 tsp vanilla extract

250g light muscovado sugar

250g plain flour

1 tsp bicarbonate of soda

2 tsp baking powder

50g cocoa powder

FOR THE CUSTARD

250g golden caster sugar

500ml full-fat milk

140g chocolate,

85% cocoa solids, broken into cubes

50g cornflour

2 tsp espresso powder

2 tsp vanilla extract

1 Bring all the custard ingredients, except the vanilla, gently to a boil, whisking until it forms a thick custard (about 5-7 mins from cold). Stir in the vanilla and a generous pinch of salt, then scrape the custard into a wide, shallow bowl. Cover with cling film, cool, then chill for at least 3 hrs or until cold and set.

2 Heat oven to 180C/160C fan/gas 4. Butter and line the bases of two 20cm sandwich tins. Melt the butter, remove from the heat and beat in the oil, buttermilk, coffee and eggs. In a bowl, whisk the dry ingredients with ¼ tsp salt (this saves sifting). Tip in the wet ingredients and whisk until smooth.

3 Divide the batter between the tins and bake for 25-30 mins until risen and a skewer inserted into the middle of the cakes comes out clean. Leave for 10 mins, then transfer to a rack to cool, parchment-side down.

4 Remove the parchment and trim any domed cakes flat. Cut each across the middle with a serrated knife, then pulse one to crumbs in a processor and add to a bowl.

5 Spread one layer with a quarter of the custard. Sandwich the next layer on top, add custard, then add the final cake layer. Spread the remaining custard over the top and sides until smooth. Chill for 15 mins to firm.

6 Hold the cake over the crumbs and gently press all over. Chill for at least 2 hrs, and eat it cold. The cake gets fudgier the longer you leave it. Can be made up to 2 days ahead.

PER SLICE

548 kcals, fat 27g, saturates 12g, carbs 68g, sugars 47g, fibre 3g, protein 7g, salt 0.6g