1 shop-bought sponge cake tart shell 30cm diameter available in produce or bakery departments
• 50ml chilled limoncello liqueur
• 250ml double cream
• 250g mascarpone cheese
• 80ml lemon curd
• 250g raspberries
• 250g blackberries
• 2 tsp lemon zest
• Handful of very thinly sliced mint leaves