Begin by cutting the seedless watermelon into bite-sized cubes. If using fresh watermelon, add ice cubes for a frosty texture. If using frozen, skip this step.

In a high-powered blender, combine the watermelon, Greek yogurt, coconut water, and lime juice. Add honey or maple syrup if desired.

Blend on high for 30 to 60 seconds until the mixture is creamy and frothy, with no visible watermelon chunks.

Check the consistency; add more coconut water if too thick or more watermelon/yogurt if too thin.

Taste the smoothie and adjust sweetness by adding more honey or syrup if needed, then blend for another 10 seconds.

Pour the smoothie into tall glasses and serve immediately, garnished with mint leaves or fruit slices if desired.