Begin by bringing the milk to a boil on medium-high heat on the stove, stiring occasionally and not letting the milk catch on the bottom of the pan. Remove from the heat. See Photo 1.

Whisk the egg yolks in a mixing bowl before adding in the flour, cornflour/starch sugar. Beat well until combined with minimal lumps. See Photo 2.

Add 1 or 2 spoons of the hot milk to the egg mixture whisk to combine. This is tempering - gradually adding introducing the hot mixture to the room temperature egg mixture. See Photo 3. This prevents scrambling the eggs. Add 1 more spoon of the milk to the egg mixture and mix again.

Next add all the egg mixture into the pan of milk, and mix well.

Return the pan to the hob, and on a low-medium heat, simmer the mixture gently. Whisk it regularly till it thickens. Note it will thicken more later.

Remove from the heat, add in the Vanilla Extract extract butter, and beat together well. Dont worry about lumps, just beat as well as you can. See Photo 4.

Push the pastry cream through a sieve into another bowl, to remove any lumps and leave a smooth silky mixture. See Photo 5 6.

Allow the cream to cool down completely. Cover the pastry cream with cling film/plastic wrap. This prevents a crust forming on the top of your pastry cream. To do this, lift the cling film/plastic wrap and position on the surface of the cream, as opposed to just covering the bowl. See Photo 7 below.

Place in the fridge, and your creme pat will thicken more with time be ready to use once cooled down. Use in pastries, cakes etc.

Will be fine for up to 3 days stored in the fridge appropriately.