Perfect Pecan Pie - Crystal Sugar

Ingredients

• 1/2 cup (1 stick) unsalted butter
• 1 cup Crystal Sugar Extra Fine Granulated Sugar
• 1 teaspoon vanilla extract
• 1 cup chopped pecans
• 1 tablespoon all-purpose flour
• 2 eggs, whites separated from yolks
• 9-inch pie crust, defrosted