Making crema pasticcera does require care, because it can curdle as it thickens, and wife Elisabetta remembers that though her mother let her beat the yolks when she was little, many years passed before she was allowed to stir the mixture over the burner as it thickened.
Crema pasticcera is more of a procedure than a recipe: Depending upon what you are making you start with more or fewer yolks, and the proportions of the other ingredients follow. To make about 3 cups (750 ml) of pastry cream, which will be enough to fill a layer cake or make a small Zuppa Inglese (English trifle), you will need:
- The yolks of 6 very fresh eggs
- 6 tablespoons (40 g) flour
- 3/4 cup (150 g) sugar
- A vanilla bean, or 1/2 teaspoon vanilla extract
- 1 pint (500 ml) whole milk
- A pinch of salt