Slice the watermelon in half. Assuming your watermelon isn’t seedless, slice the halves into smaller strips and use a small spoon to scoop out the seeds. Discard the seeds, and scoop chunks of watermelon from the rind into the blender. If the watermelon is seedless, use a big spoon to scoop chunks of watermelon flesh into the blender. Discard the rind.

Blend the watermelon until it is totally pulverized. This shouldn’t take more than a minute. Squeeze the juice of one small lime into the blender and blend for a few seconds. If your watermelon is notably pulpy, pour the mixture through a fine mash strainer into a pitcher. If not, you can pour it directly into glasses filled with ice.