Cut rind (both green and white) off entire watermelon. Make a slice through the bottom to make a base so it will remain steady on a plate. Cut watermelon the size and shape you want your cake. (A flat top cake is easier to garnish with fruit.) Pack paper towels around the entire watermelon to soak up watermelon juice. Refrigerate with paper towels for 1 hour. (The dryer the watermelon, the easier it will be to frost.) Make the Stabilized Whipped Cream Frosting. For each cup of whipped cream used, add 1 tablespoon of instant vanilla pudding and 1 tablespoon of powdered sugar. For sweeter frosting, add more powdered sugar. Whip together until stiff peaks form. Frost cake with spatula or use a 14” or 16” piping bag with large star tip. Frost the entire cake with whipped cream frosting, or just slice in layers and frost the tiers. Decorate with additional fruit. Keep watermelon cake refrigerated until ready to serve. Serve in wedges.