Put the milk, sugar and cream in a large pan over a low-medium heat, then stir continuously for 10 minutes, or until the sugar has dissolved and the liquid is steaming.
Stir in the tea leaves, then remove from the heat and cover. Leave the tea to infuse for 10 minutes.
Carefully pour the mixture through a sieve into a bowl, squeezing the loose tea really well to extract all the flavour. Discard the leaves and set the liquid aside.
In a large bowl, whisk the egg yolks until light and fluffy. Slowly add the milk mixture, whisking continuously (so it doesnât split) until combined.
Return to the pan and stir over a medium heat for around 5 minutes, or until the mixture has thickened and coats the back of the spoon, like custard.
Place in an ice-cream machine and churn according to the manufacturerâs instructions, until chilled and starting to solidify.
Transfer the ice cream to a container and put in the freezer until completely frozen.
Remove from the freezer 5 minutes before serving to allow it to soften slightly, then serve topped with crumbled shortbread.
