Buttermilk Pie

INGREDIENTS

• :
• 1¼ cups all-purpose flour
• 1 tablespoon sugar
• ½ teaspoon salt
• 4 tablespoons vegetable shortening, cut into small pieces and chilled
• 6 tablespoons unsalted butter, cut into small pieces and chilled
• 3 to 4 tablespoons ice water
• 1 egg white, lightly beaten
• ¾ + 2 teaspoons cup granulated sugar, divided
• 1 tablespoon cornstarch
• ¾ teaspoon salt
• 2 eggs
• 5 egg yolks
• 1¾ cups buttermilk
• ¼ cup heavy cream
• 4 tablespoons unsalted butter, melted
• 2 teaspoons distilled white vinegar
• 1½ teaspoons vanilla extract