When the heat is on and only an açaí will do, chances are you'll be halfway, at least mentally, to the beach. Which is handy, because Big Polis only operates in close proximity to the sand, sea and surf of Copacabana, Leblon and Barra. The great, semi-frozen folds of the Amazonian super food (if you believe the rumours) pour out of the cup in enticing style, putting a sugary skip in your step. Team it with a fresh if not fantastic sandwich or simple cheeseburger (the jacket potatoes and stroganoffs aren't really worth the extra investment), for here the key really is to go fast and go home.