- 16 oz seeded, blended watermelons
6 oz tequila
3 oz triple sec
1 tbsp sugar
Cut up a watermelon, removing seeds. Liquify in a blender until you have about 16 oz. Add remaining ingredients, top with ice and blend until smooth. Taste and add sugar if watermelon is not sweet enough. Serve in a margarita glass with a sugar-coated rim.