Whisk together egg yolks and 1/3 cup sugar in a large bowl 3 minutes or until blended.
Bring milk and remaining 1/3 cup sugar to a boil in a medium saucepan, whisking constantly.
Stir about one-fourth of hot milk mixture gradually into yolks; add to remaining hot mixture, stirring constantly. Cook over medium-low heat, stirring constantly, 10 minutes or until custard is thick enough to coat back of a wooden spoon. Remove from heat. Pour through a fine wire-mesh strainer into a bowl. Stir in brandy and vanilla.