Slice 5 rounds of melon from the “fattest” part of the melons. You want two watermelon cross sections, and then two honey dew and one cantaloup (or if you like orange more than green, two cantaloup and one honey dew).
Level the cross sections using your chef’s knife to make sure that when you stack them, they create a level tower.
Using your large circle cutter (we used a vase, but you could use a cake round), punch the rounds so they are all the same size and without skin.
Using the smaller circle cutter, punch out the centers of the seeded melons (honey dew and cantaloup). You will be left with 3 rings and two circles (watermelon).
Pat the melon rounds with paper towel to remove excess moisture.
Place one watermelon round on your cake plate. Top with a honey dew ring, then a cantaloup ring, alternating until all your are left with is the other watermelon round.
Fill the cavity with whipped cream/topping.
Top with remaining watermelon round.
Gently frost “cake” with buttercream using offset spatula. This requires a little patience, but once you have a thin layer established, it gets easier.