Buttermilk Pie | America's Test Kitchen

Ingredients

• 1 (9-inch) single-crust pie dough
• 1 large egg white , lightly beaten
• 3/4 cup (5 1/4 ounces/149 grams) plus 2 teaspoons sugar
• 1 tablespoon cornstarch
• 3/4 teaspoon salt
• 2 large eggs plus 5 large yolks
• 1 3/4 cups 1 percent low-fat buttermilk
• 1/4 cup heavy cream
• 4 tablespoons unsalted butter , melted and cooled
• 2 teaspoons distilled white vinegar
• 1 1/2 teaspoons vanilla extract