How to Make It
Preheat oven to 400°.
Lightly spoon flour into dry measuring cups; level with a knife. Combine flour, pumpkin pie spice, baking soda, ginger, and salt in a medium bowl, stirring well with a whisk. Stir in raisins; make a well in center of mixture. Combine brown sugar, canned pumpkin, buttermilk, canola oil, molasses, vanilla extract, and eggs, stirring well with a whisk. Add sugar mixture to flour mixture; stir just until moist.
Spoon batter into 18 muffin cups coated with cooking spray. Sprinkle with granulated sugar. Bake at 400° for 15 minutes or until a wooden pick inserted in center comes out clean. Remove muffins from pans immediately; cool on a wire rack.