Melt 1/4 cup butter in 10-inch cast iron skillet over low heat; stir in rum. Sprinkle brown sugar evenly over butter mixture. Remove from heat.
Sprinkle pecans evenly over brown sugar mixture. Cut bananas in half crosswise; cut each half lengthwise into 3 slices. Arrange banana slices in a spoke pattern over pecans. Cut 6 cherries in half. Place one cherry half between each banana slice. Place the remaining whole cherry in the center of skillet.
Beat remaining 1/4 cup butter and 1/2 cup sugar in a large bowl at medium speed with an electric mixer until blended. Add egg yolks, 1 at a time, beating just until blended afer each addition. Add milk, sour cream and vanilla, beating just until blended. Combine baking mix and cinnamon. Add cinnamon mixture to milk mixture, beating just until blended.
Beat egg whites in a large bowl with an electric mixer until soft peaks form. Gradually beat in remainign 1/4 cup sugar until stiff peaks form. Fold into batter. Spread batter evenly over bananas in skillet.
Bake at 350 degrees for 45 to 50 minutes or until a wooden pick inserted in center comes out clean. Cool in skillet on wire rack for 10 minutes. Invert onto a serving plate. Serve warm with whipped cream, if desired.