Martha Stewart's Watermelon Basil Margaritas Recipe. Ingredients Ingredients on sale Currently these ingredients aren't on sale near you. 7 1/2 pounds seedless watermelon, rind removed, fruit cut into 1-inch cubes 4 teaspoons superfine sugar 6 ounces (3/4 cup) silver tequila 24 basil leaves, plus sprigs for garnish 3 ounces (1/4 cup plus 2 tablespoons) triple sec 6 cups small ice cubes Directions #1. Add 24 watermelon cubes on a baking sheet lined with wax paper. Cover, and freeze at least 1 hour (up to 2 days). #2. Mix and Puree left over watermelon and sugar in a blender until smooth. filter through a sieve lined with cheesecloth into a bowl. This should make 3 cups. #3. Pour tequila and basil in a glass pitcher, and crush with a wooden spoon. Stir in watermelon juice and triple sec. #4. Add watermelon cubes in glasses. Using a cocktail shaker, mix 3/4 cup margarita with 1 cup ice. Strain into a glass. Repe...