• Pour the passion fruit juice into a large saucepan and cook over medium heat, stirring constantly. Continue to cook for about 15 to 20 minutes until it reduces to 1 cup. Set aside while you prepare the custard.
• Place a strainer on top of a bowl and set aside. 
• Add the milk, cream, 3/4 cup of sugar, and the salt to a saucepan over medium heat. Stir until the mixture is warm.
• In a separate bowl beat the yolks with the remaining 1/4 cup sugar.
• Whisk a cup of the warm milk mixture into the yolk mixture. Continue whisking until well combined then pour it into the saucepan with the rest of the warm milk mixture. 
• Stir the mixture constantly while you heat it over medium heat. Continue heating and stirring until an instant-read thermometer reads 160°-180°F. (make sure the mixture does not boil).
• Pour the custard into the strainer that is set over a bowl to remove any bits of cooked egg yolk.  
• Stir in the vanilla and the passion fruit then cover the mixture and place it in the fridge to chill. 

Ice cream machine:

• Pour the custard into an ice cream maker and follow the manufactures instructions for churning ice cream. 
• Transfer the ice cream to an airtight container and freeze for 3 to 4 hours.