Butterscotch Pie

INGREDIENTS

• 1 cup heavy cream
• 1/2 teaspoon salt
• 1 (9-inch) pre-baked pie shell
• 1 1/2 cups brown sugar
• 1/4 cup powdered sugar
• 1/2 cup all-purpose flour
• Whipped cream, recipe follows
• 2 egg yolks, lightly beaten
• 4 cups milk
• 1 tablespoon cornstarch
• 1/4 cup butterscotch morsels, plus more for topping
• 2 tablespoons butter
• 2 teaspoons vanilla extract