Crush the biscuits into fine crumbs and stir in the caster sugar.
Mix in the melted butter and press the mixture into a 23cm springform tin, building 4cm sides.
Chill the crust in the fridge for 20 minutes until firm.
Preheat your oven to 170°C.
Whisk condensed milk, lime juice, zest, cordial, egg yolks, and 100ml of cream until thick.
Pour the filling into the crust and bake for 15 to 20 minutes until slightly wobbly.
Cool for 30 minutes in the tin, then refrigerate until cold.
Whip the remaining 100ml of cream with icing sugar until soft peaks form.
Spread the cream over the pie and garnish with mint before serving.