To make curd, cut the cheeks from 1 mango. Using a large spoon remove the mango fruit from the cheeks. Puree mango until smooth. You need ¾ cup. Whisk egg yolks and sugar in a 6-cup capacity heatproof, microwave-safe bowl until combined. Whisk in ½ cup lemon juice. Add the butter. Microwave, uncovered, for 6-7 minutes on Medium/50%, whisking every minute, until the curd thickens and just comes to the boil. Stir in mango puree. Cover surface with plastic wrap. Refrigerate for 2 hours.
Spoon the ice-cream into a large bowl. Stand at room temperature for 10 minutes, or until softened slightly. Fold in 1 cup of mango curd. Spoon into a 12cm x 22cm (base) loaf pan. Cover and freeze overnight.
Process biscuits and pistachios until finely chopped. Stir in coconut. Cut the cheeks from the remaining mangoes. Using a large spoon remove the mango fruit from the cheeks and cut into 2cm cubes.
To serve, spoon half the biscuit mixture into the base of six serving glasses. Top with scoops of ice-cream and half the mango. Repeat layers. Serve.