How to make
In a suitable container, heat the milk with half the sugar. Just warm it, don't boil it.
In a bowl, beat the egg yolks with the remaining half of the sugar and add the flour and about 3.4 fl oz (100 ml) of cold milk, stir well until a homogeneous mixture is obtained, then strain the mixture, so that there are no lumps.
Add the egg mixture to the warm milk in a thin stream, by stirring constantly. The egg custard is boiled over medium heat on the stove, by stirring constantly. Boil for about 4 or 5 minutes, by stirring constantly.
After taking it off the heat, finely chopped butter and vanilla are added to the homemade custard and it is stirred, so that the butter melts.
The finished custard can be put in a suitable container, sprinkled with powdered sugar and place a cling film on top and it can be left in the refrigerator for about three days, this is its maximum shelf life. Homemade custard is suitable for use for homemade cakes, biscuit cakes, sweet eclairs and can be consumed on its own.
PS: in the recipe for homemade custard for cakes, the flour can be replaced with starch and for a different flavor, cinnamon or rum can be added.