1 refrigerated pie crust (from a 15-ounce package)
1 1/2 cups sugar
3 tablespoons all-purpose flour
1 cup buttermilk
1 teaspoon vanilla extract
1/4 cup (1/2 stick) butter, melted
1/2 teaspoon ground cinnamon
Directions1.Preheat oven to 425 degrees F. Place pie crust in a 9-inch pie plate and flute edges; set aside.
2.In a large bowl, whisk sugar, flour, and buttermilk. Add eggs, vanilla, and butter and whisk until thoroughly combined. Pour into pie shell; sprinkle evenly with cinnamon.
3.Bake 10 minutes, then reduce oven to 325 degrees and continue baking 35 to 40 minutes, or until a knife inserted in center comes out dry.