Line 24 muffin cups in regular-sized muffin pans with paper baking cups.
In a large bowl, combine flour, baking powder, cinnamon, pumpkin pie spice, baking soda, and salt. Blend well; set aside.
In a large mixing bowl, combine butter and sugar. Beat until light and fluffy.
Add eggs, one at a time, beating on low speed after each addition.
Add sweet potatoes, vanilla, and orange extract, beating until combined.
Add flour mixture to mixing bowl, and beat until just combined.
Divide batter evenly among muffin cups, filling about 2/3 full.
Bake at 350 degrees for about 18-20 minutes, or until tops spring back when lightly touched.
Cool completely on a wire rack.