Watermelon Lime Frosty (or Margarita) And Guess What? by Watermelon Lime Frosty (or Margarita) And Guess What?The secret in this one is the frozen banana because it makes the whole drink creamy and thick when added to the juicy watermelon. It works really well along with the lime juice and zest to create a perfect little summer treat.Watermelon Lime Frosty (or Margarita) adapted from Happy, Healthy, Life makes 2 3 cups watermelon, cubed and frozen 1 ripe banana, peeled and frozen 2 tablespoons agave nectar or maple syrup Zest from 2 limes Juice from 2 limes (about 4 tablespoons) 1/2 cup water Blend all ingredients until smooth, adding more water as needed to keep the mixture moving. For margaritas: add 3-4 shots of silver tequila