Line a 9-inch round cake pan with parchment and spray with cooking spray. Set aside.
In a small saucepan, melt butter. Stir in brown sugar until dissolved. Pour mixture into bottom of cake pan. Arrange sliced bananas in the bottom of the pan. Set aside.
In a large bowl, add egg whites and cream of tartar, and beat on high until soft peaks form. Set aside.
In a separate large bowl, cream together butter and sugar until light and fluffy. Add egg yolks, vanilla and milk; beat until combined. Slowly add flour, salt, baking powder, ginger and cinnamon. Using a rubber spatula, fold in the egg whites until mixture is smooth.
Pour batter into prepared pan. Bake 35 to 40 minutes or until a toothpick inserted into the center comes out clean. Allow to cool, then flip pan to remove loaf. Slice and serve.