Watermelon Daiquiri

Process chopped watermelon in a blender until smooth, about 30 seconds. Pour processed watermelon through a fine wire-mesh strainer into a medium bowl to yield 1 1/2 cups watermelon juice (enough for 8 cocktails). Discard solids. Chill juice until ready to make cocktails.

Salt half the rim of a chilled coupe glass. Add white rum, lime juice, agave nectar, and 3 tablespoons watermelon juice to a cocktail shaker filled three- fourths of the way with ice. Cover and shake vigorously until well combined, about 10 seconds. Strain into coupe glass. Garnish with a watermelon slice.