Cut the watermelon into the shape of a cake by cutting away the rind and making the top and bottom flat. (See video for further tips on cutting.) Place the watermelon on your serving plate. If you watermelon is very juicy, lightly blot the outside with a paper towel to remove extra moisture before adding the whipped cream.
To make the whipped cream frosting, place the heavy cream in the bowl of your stand mixer. Add the powdered sugar and vanilla. Whip on high until peaks form, about 3 minutes.
Cover the outside of the watermelon with the freshly whipped cream. Decorate with toasted coconut and sprinkles.
Video
Notes
Be sure to use heavy whipping cream or heavy cream (they are the same) because it’s more stable and stays whipped better than regular whipping cream.
If your watermelon is too wet, the frosting will not stick to the watermelon cake so take the time to soak up some of the excess moisture with some paper towels.
Feel free to get creative with your decorations - berries and chopped nuts are another beautiful way to decorate this cake.
Store the cake in the fridge until ready to serve.