Peel, pit and chop the mangoes. In a food processor, puree the mango, stopping once or twice to scrape down the sides of the work bowl. There should be about two cups of puree.
3
In a pitcher, combine the mango puree, water, lemon juice and sugar; stir well to dissolve. Cover and refrigerate until very cold, at least 5 hours and preferably overnight.
4
Taste, and add more sugar if desired. Pour lemonade over ice in tall glasses. Garnish with mint.