To make the basic custard:
In a thick-based saucepan over a medium to low heat mix together the milk and cream. Scrape in the vanilla seeds and bring to a simmer.

Beat the egg yolks and the caster sugar for 10 minutes, or until pale and creamy. Add a little of the warm cream mixture to the egg mixture and mix to combine, then spoon the egg mixture into the cream mixture and cook gently, stirring continuously.

When nearing a boil, remove from the heat, strain and leave to cool.

To make the caramel:
In a thick-bottomed pan over a medium to low heat mix together the sugar and water and slowly bring to a boil.

To make the ice cream:
When the caramel is fragrant and dark in colour, stir it into the custard, along with the Maldon sea salt, and leave to cool. Pour the mixture into a rectangular container and freeze. Once frozen, remove from the freezer and beat.

Freeze again until completely set. (Alternatively pour the mixture into an icecream machine and churn according to the manufacturer’s instructions.)