These refreshing slushies are so easy to make, it's not even funny. I used about a quarter of a medium watermelon and about equal parts ice. I'd say about 2 cups of each got thrown into our blender and out came this cool, icy watermelon slush. Just what I needed after a busy morning running errands. This is a great drink to make for all these weekend BBQ's this beautiful weather is calling for lately!