Instruction

• Heat the oven to 180C/160C fan/gas 4
• Butter and line a 23cm springform cake tin
• Tip 150g of the pistachios into a food processor and blitz until finely ground
• Tip into a bowl and mix in the flour, baking powder and pinch of salt
• Beat the butter and sugar in a separate bowl until fluffy and pale, around 5 mins
• Crack in the eggs one at a time, beating well for 1 min after each addition, until they have all been added
• Beat in the vanilla, then fold in the flour mixture gently
• Carefully spoon into the prepared tin and bake for 35-40 mins until a skewer inserted into the middle comes out clean
• Set aside to cool completely on a wire rack in the tin
• step 2 Meanwhile, sift the icing sugar into a bowl, then tip in the mascarpone, double cream and pistachio paste
• Beat until well combined, then set aside in the fridge for 20-30 mins to thicken to a spooning consistency
• step 3 Cut the cooled cake in half horizontally using a serrated knife, so you have two layers
• Put the bottom layer on a plate or cake stand and spread over a generous spoonful of the pistachio cream
• Top with a generous handful of the raspberries so the cake is covered
• Top with the other sponge half, then cover the top and sides of the cake with the remaining cream
• Scatter over the last of the raspberries, the remaining pistachios and the lime zest to serve
• Will keep chilled in an airtight container for two days