The pie filling ranges in color from orange to brown, and is baked in a single pie shell, rarely with a top crust. The pie is generally flavored with cinnamon, powdered ginger, nutmeg, and cloves. Allspice is also commonly used and can replace the clove and nutmeg, as its flavor is similar to both combined. Cardamom and vanilla are also sometimes used as batter spices. The spice mixture is called pumpkin pie spice.