An unassuming little kiosk at the end of one of Barra's more interesting (read less residential) streets, Açaí Tropical churns out one of the best cups of the frozen purple superfood in the neighbourhood. Delivered straight from a machine, the pure form will satisfy traditionalists, nicely light on the super-sweet guarana syrup that usually buries the berry's health benefits under a sugary coating. Order a cup of Tropical (R$9 for 300ml), though, and choose from pots of additional ingredients like condensed milk, granola, crispy rice balls or the excellent crushed peanuts. Simple chicken and tuna sandwiches are also served on a variety of breads from panini to wraps.