In a large bowl, whisk together egg yolks, cornflour, half of the granualted sugar, vanilla bean paste, and fine sea salt. Set aside.

In a medium saucepan, combine milk and remaining sugar. Stir to dissolve the sugar, then warm mixture over medium heat until steaming. (Do not boil).

Gradually pour the hot milk into the egg mixture in a thin stream, whisking well after each addition. Do not to pour too quickly or add all of the milk at once.

Pour egg mixture back into saucepan. Cook over medium-low heat, stirring continuously with a flexible rubber spatula or silicone whisk, about 8-10 minutes or until pudding thickens, deepens in color, and coats the back of a spatula or spoon.

Bring to a low boil. Boil for 2 minutes, stirring continuously.

Remove from heat. Whisk in the butter, and continue whisking until completely melted.

Allow pudding to cool, whisking occasionally, for 10 minutes or until pudding stops steaming. Pour into small serving bowls or ramekins.

Cover each portion with clingfilm/plastic wrap, allowing the plastic to touch the pudding to prevent a tough “skin” from forming on top. Refrigerate for at least 3 hours, or until ready to serve.

Store leftover vanilla pudding in the refrigerator for up to 2 days.