Whisk together egg yolks, sugar and salt in a small heat-safe bowl.

Add in the cornstarch, all-purpose flour and vanilla extract and whisk to combine.

In a small saucepan, heat up whole milk until scalding hot (don't let it boil).

Temper the eggs by gradually pouring the warmed milk in a stream, while constantly whisking, until all the milk is added to the egg mixture.

Pour the mixture back into the pot and cook over low heat, until thickened and reaches a temperature of 175F.

Remove from heat and strain through a sieve into a clean container.

Place a piece of parchment paper over the top of the cream.

Cool completely, cover and chill in the fridge until ready to use.