Pastry Cream

Adapted from Pastry Cream

Yield: 3 cups; 5 cups with the optional whipped cream

3 cups whole milk
1/2 cup sugar
1/4 teaspoon salt
2 teaspoons vanilla extract; or 1/2 vanilla bean, slit lengthwise
1/3 cup cornstarch
4 large egg yolks
4 tablespoons (1/4 cup) butter
Optional for a softer filling: 1 cup heavy cream, whipped to soft peaks

1. In a medium-sized saucepan, stir together 2 1/2 cups of the milk, the sugar and salt. Bring to a simmer over medium heat, stirring to dissolve the sugar.
2. Meanwhile, whisk the cornstarch, flour, and egg yolks with the remaining 1/2 cup milk.
Whisk some of the hot milk mixture with the egg yolks to temper them. This keeps the yolks from turning to scrambled eggs when you add them to the simmering milk.
3. Pour the egg/milk mixture back into the remaining simmering milk. Doing this through a strainer will help prevent lumps later. Bring to a boil, stirring constantly with a whisk, until the mixture thickens.
4. Remove from the heat and strain through a fine strainer into a bowl set in an ice bath. Stir in the butter and vanilla extract.
5. Rub a piece of butter over the surface of the cream, top with a piece of plastic wrap (make sure it touches the top of the pastry cream so it doesn't develop a skin), then refrigerate until cool.
6. Use chilled pastry cream as is for a sliceable cream pie, or a stiff filling for éclairs. Fold in the optional whipped cream, just before using, for a softer filling.

Pastry cream will keep, covered in the refrigerator, for up to 5 days. After that it may start to weep.