1. Cook milk in a heavy nonaluminum saucepan over medium heat, stirring often, 10 minutes or just until it begins to steam. (Do not boil.) Remove from heat.
2. Whisk together eggs and next 3 ingredients until blended. Gradually whisk 1 cup hot milk into egg mixture; whisk egg mixture into remaining hot milk, stirring constantly.
3. Cook over medium heat, stirring constantly, 8 to 10 minutes or until a thermometer registers between 170° and 180°. (Do not boil.)
4. Remove from heat, and pour mixture through a fine wire-mesh strainer into a bowl. Place heavy-duty plastic wrap directly on warm custard to prevent a film from forming on top, and chill at least 24 hours or up to 3 days. Mixture will thicken as it cools.