Heat milk, cream and vanilla in a heavy-based saucepan until at simmering point
Beat egg yolks with sugar until pale and thick
Slowly whisk hot milk mixture into the egg mix
Clean the saucpan and return mixture to the heat, stirring constantly until thickened to a custard
Pour custard into a heatproof bowl, cover and chill until cold
Mix the custard with the passion fruit pulp and chocolate chunks, then pour into an ice-cream maker to churn until desired consistency is met.