Using a hand or stand mixer, cream butter and brown sugar together until light and fluffy. Add egg and molasses, mixing well.
Combine dry ingredients in a separate bowl: flour, baking soda, spices and salt. Add to creamed mixture about ½ cup at a time. Mix well.
Chill for at least half an hour or up to 48 hours. Preheat oven to 350 degrees F.
Shape dough into 1.5 inch balls (about the size of a ping pong ball) and roll in granulated sugar. Place on parchment paper lined cookie sheet 3 inches apart.
Bake for 10-12 minutes on the middle oven rack, until the edges are set and golden. The center will appear slightly underdone. Let rest on the cookie sheet for 5 minutes before transferring to a cooling rack.
