Berry & pistachio cakes

1. Preheat the oven to 180ºC, gas mark 4. Line a 12-hole muffin tin with paper cases. Blitz the pistachios and icing sugar together in a food processor until finely ground, then add to a large bowl with the plain flour, baking powder, orange zest and a pinch of salt.

2. Whisk the egg whites in a clean bowl until forming soft peaks. Stir the melted butter into the dry ingredients, mixing well to combine, then gently fold through the whisked egg whites.

3. Divide half the batter between the cases, then drop most of the berries on top.

4. Add the rest of the batter and finish with the remaining berries. Bake in the oven for 20-30 minutes or until a skewer inserted into the centre comes out clean. Leave to cool for 5 minutes, then remove from the tin and place on a wire rack. Dust with icing sugar before serving warm or cold.