Southern Buttermilk Pie

Name: Southern Buttermilk Pie
Prep time: 15 min
Cook time: 1 h
Total time: 1 h 15 min
Cuisine: American, Southern
Ingredients: 1/2 cup unsalted butter, room temperature; 2 cups sugar; 3 large eggs; 1 cup buttermilk; 3 heaping tablespoons all-purpose flour; 2 teaspoons vanilla extract; pinch of salt; dash of nutmeg; 1 prepared deep dish pie crust, unbaked