Peel and slice 6 medium carrots about 1 inch thick. Cover with water and boil until just barely tender. Drain. Place in casserole, sprinkle with 1/2 cup brown sugar and 1/2 teaspoon cinnamon. Slice 1/2 stick butter over top. Place at 375 degrees. Bake 10 minutes. Cover casserole and bake about 20 minutes.