Line the base and sides of a 22cm spring-form pan with non-stick baking paper (see tips)

Place ice-cream in a large mixing bowl and set aside to slightly defrost. Using a large metal spoon, stir in custard until combined. Add meringues, pistachios and about three quarters of the chocolate

Stir to combine. Gently stir through 3 cups (375g) frozen Raspberries. Spoon mixture into prepared pan and smooth top. Sprinkle with 1 cup (125g) frozen Raspberries and gently press into mixture

Cover with plastic wrap and freezer overnight

To serve, remove ice-cream cake from pan and place on a serving plate (you may need to stand it for a short time if it's frozen very firm). Top with remaining frozen Raspberries, sprinkle with remaining grated chocolate and serve