Place the seedless watermelon chunks into the blender.
Squeeze the juice of a fresh lime directly into the blender, adding a bright, tangy flavor.
If you like it sweeter, add a tablespoon or two of honey or agave syrup and let the blender spin for a few seconds to incorporate.
Add a cup of ice cubes to the blender, which will help chill and thicken the smoothie as it blends.
Secure the lid on the blender and blend on high for about 30-45 seconds, until the mixture is smooth, frothy, and vividly pink.
Pour the thick, icy watermelon smoothie into glasses, watching the vibrant color spill over the rim.
Garnish with a small wedge of lime or a sprig of mint for a fresh finishing touch.
Serve immediately with a straw, enjoy the chilled, refreshing burst of summer flavor.