Preheat oven to 400 degrees.
Grease muffin tins that are 2 1/2 " in diameter.
Cream the butter (or margarine) and sugar until light and fluffy. Beat in the eggs and pumpkin. Dredge the onions with a cup of flour.
Sift 3 cups of flour and the baking powder, cinnamon, nutmeg, and salt together. Add the dry ingredients and milk alternately by hand, mixing until just blended. Do not over mix. Add the raisins.
Spoon into the prepared muffin tins, filling each tin 3/4 full. Bake at 400 degrees for 20 to 25 minutes.