Cut the watermelons in half and use a larger melon baller to remove small balls. Then cut off a thick slice and pull out additional balls until the halves of the melon are completely used.
Carefully remove any visible seeds from the balls. Puree the remaining fruit flesh, strain, and serve as a cold melon soup, refined with sherry, for example.

Now place the melon balls into a bowl and pour both types of sherry over the melon balls. Add the salt, sprinkle coarsely ground pepper on top, and add mint leaves. Mix the fruit, place them next to each other in a boil-proof bag, and vacuum with 100%.

Cook in the sous vide water bath for 20 minutes at a temperature of 62 °C, then cool in ice water. Allow to infuse for 1-2 days before serving.