Begin by selecting a ripe watermelon for the best flavor. Cut the watermelon into quarters and carefully remove the skin. Dice the watermelon flesh into manageable cubes, discarding any visible seeds.

Next, take a piece of fresh ginger and peel off the skin. Finely grate or chop the ginger until you have about two teaspoons.

Cut a fresh lime in half and squeeze each half firmly to extract the juice, straining any seeds out as you do.

In a blender, combine the diced watermelon and grated ginger. Blend on high speed until smooth and creamy, about 30 seconds.

Pour in the freshly extracted lime juice and blend again for another 10-15 seconds to incorporate the juice.

Transfer the blended mixture to a pitcher and chill in the refrigerator for at least 30 minutes.

After chilling, pour the cooler into tall glasses and garnish with lime slices or fresh rosemary or basil.