Heat oven to 350 degrees F. Line muffin pan with 12 paper liners. Set aside.
In a large bowl, stir together muffin mix, water, oil, egg, and pumpkin pie spice with a rubber spatula until blended. Do not over-mix. Fill muffin cups 2/3 full.
Bake 14–16 minutes, or until a toothpick inserted in center comes out clean or with moist, not wet, crumbs.
Cool for about 15 minutes.
In a medium bowl, whisk together the maple syrup, milk, and powdered sugar until a soft icing forms. Dip the tops of the muffins into the icing and allow the excess icing to drip off. Return the muffins to a wire rack to set the icing.