Flourless chocolate and espresso cakes

Method

1. Grease the springform tins and line with baking paper. In a small saucepan, melt the butter and chocolate together over a very low heat. Once completelymelted, stir in the espresso powder. Take off the heat and add the ground almonds.
2. Separate the egg. In a spotlessly clean bowl, whisk the white and, as it begins to froth, add half the caster sugar a spoonful at a time, whisking all the while, until you have a glossy and stiff white mass, like meringue. In a second bowl, whisk the yolk together with the remaining sugar until it has doubled in volume and turned a pale, creamy shade of yellow. Gently fold the white into the yolk, then fold in the melted chocolate mixture.
3. Heat the oven to 140°C fan/gas 3. Divide the cake batter equally between the prepared tins and bake for 20-25 minutes. The cakes should be dry on top and feel firm to the touch. To test if they’re done, insert a toothpick or knife to the= middle; it won’t come out completely clean, but the cake should be crumby rather than liquid.
4. Leave to cool for at least 10 minutes in the tin and serve either warm or at room temperature, dusted with icing sugar and/or with crème fraîche or raspberries, as you like.