Place the strawberries and half of the yoghurt into a blender and purée.

Transfer the mixture to a mixing bowl and stir in the remaining yoghurt, custard and condensed milk. Fold in the whipped cream and transfer the mixture to a freezer-proof sealed container.

Freeze for 2 hours. Remove from the freezer and break up any ice crystals using a fork. Return to the freezer, and freeze until firm.