Steps

Scrape the vanilla pods and in a saucepan, heat the milk and cream with the scraped vanilla beans and pods until simmering

In a bowl, whisk the egg yolks with the sugar until the mixture turns pale

Gradually pour the hot liquids over this mixture, stirring constantly to temper the egg yolks and avoid scrambling them

Pour the mixture back into the saucepan and cook over low heat, stirring constantly until the custard thickens and coats the back of the spoon. Do not boil to avoid the cream curdling or the eggs coagulating. To check if it is cooked, dip the spatula into the cream and run your finger over it; the line should be clear. Cook to 82°C on a thermometer. Remove from the heat.

Strain through a sieve, then leave to cool in a container placed over ice cubes to stop the cooking process. Cool, stirring occasionally to prevent a skin from forming.

Cover with cling film and leave in the refrigerator for 12 to 24 hours to thicken.