1Heat oven to 350°F. In 9-inch square pan, melt butter in oven. Sprinkle brown sugar evenly over melted butter. Arrange pineapple slices over brown sugar. Place cherry in center of each pineapple slice.
2In medium bowl, beat remaining ingredients with electric mixer on low speed 30 seconds, scraping bowl constantly. Beat on high speed 3 minutes, scraping bowl occasionally. Pour batter over pineapple and cherries.
3Bake 50 to 55 minutes or until toothpick inserted in center comes out clean. Immediately place heatproof serving plate upside down over pan; turn plate and pan over. Leave pan over cake a few minutes so brown sugar mixture can drizzle over cake; remove pan. Serve cake warm. Store loosely covered.