Rich Butterscotch Pie

Bake piecrust in a 9-inch pie plate according to package directions.

In a small saucepan, heat milk over medium heat just until bubbles form around sides of pan. (Do not boil.) Remove from heat.

In a medium saucepan, melt 5 tablespoons butter over medium heat. Stir in flour, forming a smooth paste. Stir in sugars. Cook, stirring constantly, until sugars are melted and mixture is smooth. Gradually add hot milk.

In a small bowl, whisk egg yolks,. Slowly add ½ cup hot milk mixture, whisking constantly. Add egg yolk mixture to remaining hot milk mixture, and bring to a boil, whisking contantly; cook for 3 minutes, whisking constantly. Whisk in vanilla and remaining 1 tablespoon butter. Pour into prepared crust. Cover with a piece of plastic wrap, pressing wrap directly onto surface of filling, and refrigerate.

Just before serving, spread whipped cream onto filling, swirling as desired.