Watermelon mai tai

Just the thing to herald in Spring.500g seedless watermelon, cubed1 bethonga pineapple, peeled, cored and cubed180 mls white rum or Cachaca90 mls triple sec or Cointreau1 tsp grenadine.Get down the juicer and juice the watermelon and pineapple. Pour the juice and everything else over ice and stir to chill. Serve with a sprig of fresh spring mint.Inspiration comes from September Australian Good