Posh as they are, the folks behind the Downtown Crossing eatery Blu recognize that a bar menu just ain't a bar menu without fries, wings, and mozzarella sticks. Except here, of course, the fries are made from polenta and served with truffled cheese. The duck wings are cooked to a crisp, then tossed with charred jalapeos and honey. And the fried cheese? House-made smoked mozzarella slathered in spicy tomato crema and basil pesto. No nachos yet, possibly because they're still fine-tuning the artisanal guac.