A great tip that I picked up from Pastry School is that there is actually a rule to determine how long the Pastry Cream should cook.u003cbr/u003eu003cbr/u003eFor 1 litre of Milk, the cream needs to cook 1 minute. That means that if you are making a smaller batch of 250ml (1 cup) for example, you need to cook the cream for 15 seconds.u003cbr/u003eu003cbr/u003eThe cooking time starts when all the ingredients are incorporated into the pot and you see the first bubble of a boil. Cooking the Pastry Cream the right time not only allows to get the perfect custard consistency, it also makes sure that the Egg Yolks are properly cooked to avoid any risks.