Preheat oven to 400 degrees
In a large skillet, melt butter on medium heat
Add brown sugar and spices to skillet. Stir to combine
Add cubed yams to skillet. Toss to coat evenly
Brown yams on medium heat. This should take approx. 10 minutes
Transfer browned yams to an oven proof dish. Cover and bake until fork tender (about 45 minutes).