Sushi Square is more like a cube — a block of Biscayne Boulevard restaurant so tiny that you might miss it even when you're looking for it. That would be a shame, as the Square serves up fresher sushi than any of its competition in these parts. Try a roll with mango, something a little more exotic like shark, or just stick with traditional fare. Even the California Roll here is a revelation, and the fact that the back door opens out onto the Upper Eastside Garden, a popular lounge/mini-golf course, makes a visit that much more worthwhile.