Place the chopped melon flesh, lemon juice and white wine in a food processor. Pulse until you have a smooth mixture. Pass through a fine sieve into a bowl. Cover and chill until serving point.
Use a melon baller to prepare balls of watermelon. Transfer to a small bowl, cover and chill until needed. Prepare the mint sugar garnish by pounding the mint leaves and granulated sugar together until blended and even in texture. It should have a sand-like texture.
When ready to serve, ladle the melon soup into shallow ceramic serving bowls. Garnish with a few balls of the watermelon. Sprinkle the mint sugar on top and serve immediately.
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