Ingredients

Makes about 5 cups

　　3/4 cup sugar

　　3 tablespoons cornstarch

　　4 cups whole milk

　　2 teaspoons finely grated fresh orange zest

　　10 large egg yolks

　　1 teaspoon vanilla

　　

Step 1

Whisk together 1/4 cup sugar, cornstarch, and a pinch of salt in a 2-quart heavy saucepan. Whisk in 1/4 cup milk until smooth, then stir in remaining milk and zest. Bring to a boil over moderate heat, whisking frequently.

　　

Step 2

Have ready a bowl filled with ice and cold water. Whisk together yolks and remaining 1/2 cup sugar in a large bowl. Gradually whisk in hot milk mixture, then transfer custard to saucepan. Cook, stirring constantly, until mixture registers 170°F on an instant-read thermometer, 3 to 4 minutes. (Do not boil.)

　　

Step 3

Immediately pour custard through a fine sieve into a metal bowl set in ice water. Stir in vanilla. Cool, stirring frequently.

　　Cooks' note:

　　·Custard can be made 3 days ahead and chilled, its surface covered with wax paper and bowl covered with plastic wrap.