Preheat oven to 180°C. Grease 23cm square cake pan with butter. Lightly sprinkle with flour, then line base with baking parchment paper.
Heat butter and brown sugar in small saucepan over medium heat, stirring occasionally, until butter has melted and sugar is dissolved. Pour hot mixture into cake pan, and spread to completely cover base. Arrange bananas cut-sides down in pan. Place dates cut-sides up around bananas.
Beat cake mix, eggs, oil and water in large bowl with electric mixer on low speed until moistened, Beat on medium speed 2 minutes. Pour into cake pan; spread evenly.
Bake 55 to 65 minutes or until toothpick inserted in center of cake comes out clean. Immediately run knife around side of pan to loosen cake.
Place heatproof serving plate or board upside down on top of cake pan. Turn plate and pan over together. Leave pan over cake 5 minutes so brown sugar topping can drizzle over cake, then remove.
Meanwhile, beat whipping cream mix and milk in medium bowl as directed on package. Fold in ground cinnamon. Stir honey and pecans together in small bowl.
Serve warm cake, cut into squares, with honey glaze spooned over. Top with a spoonful of the cinnamon whipped cream.