Pineapple Upside-Down Cake
["1 can pineapple, sliced and drained (15 oz.)", "1/2 c. brown sugar", "1 stick butter", "yellow cake mix"]
["Melt butter in 9 x 13-inch sheet cake pan.", "Stir in brown sugar and add the pineapple slices.", "Pour prepared yellow cake mix over pineapple.", "Bake at 350\u00b0 for 30 to 35 minutes.", "Let cool, then flip cake over."]
["pineapple", "brown sugar", "butter", "yellow cake"]