This is from Duncan Hines Bake Shop in a Book, 1979. Those pineapple and cherry bits are not actually on top - they are baked on the bottom!
1 package Duncan Hines Deluxe II Pineapple Supreme Cake Mix (wish that was still around!)
1/2 butter or margarine
1 cup packed brown sugar
1 can (20 oz.) pineapple chunks, drained
Red and green maraschino cherries (about 5 each)
Preheat oven to 350F. Melt butter in a 13x9x2 pan. Sprinkle brown sugar evenly in pan. arrange drained pineapple chunks in rows, starting with 1 chunk in the first row, 2 in the second row, etc. , to form a Christmas tree shape. Use 4 chunks to make the trunk. Place red and green maraschino cherry quarters (imagine cutting those) between chunks to decorate tree. Set aside.
Make cake as directed on package, using 1 1/3 cups water and 2 eggs; do not substitute pineapple juice for water. Beat as directed. Pour batter over fruit. Bake at 350 F for 50 minutes, or until cake tests done with a toochpick. Let stand 5 minutes for topping to begin to set. Then turn upside-down onto a large platter or a cookie sheet. If desired, cut cake around pineapple to form a cut-out tree. Serve warm with whipped cream.