Preheat oven to 350°F.
Drain pineapple, reserving 5 tablespoons juice. Set aside 1 whole pineapple slice; cut 4 slices in half (reserve remainder for another use).
Melt butter in 9-inch-diameter cake pan with 2-inch-high sides over low heat. Transfer 1 1/2 tablespoons butter to small bowl and reserve; leave remaining butter in pan.
Add brown sugar and 3 tablespoons pineapple juice to pan. Stir over medium heat until mixture boils and thickens slightly, about 45 seconds. Remove from heat.
Place whole pineapple slice in center of pan atop sugar mixture. Surround with halved pineapple slices, rounded side toward pan edge. Sprinkle cherries in hollows of pineapple slices.
Mix flour and baking powder in small bowl.
Using electric mixer, beat egg whites and salt in large bowl until soft peaks form. Gradually add 1/4 cup sugar; beat until stiff peaks form.
Using same beaters, beat yolks and 1/4 cup sugar in another large bowl until well blended.
Mix in milk, vanilla and reserved 1 1/2 tablespoons butter. Beat in flour mixture just until blended. Fold whites into batter in 3 additions.
Spread batter over pineapple slices in pan.
Bake cake until golden and tester inserted into center comes out clean, about 30 minutes. Cool in pan 5 minutes.
Place platter over cake; then invert cake onto platter. Remove pan; rearrange any fruit that may have become dislodged.
Cool cake on platter 30 minutes. Brush 2 tablespoons pineapple juice over pineapple. Cool completely.