Blue Moon Burgers Inc   

In the burgeoning region of South Lake Union, this bi-level shrine to the iconic American lunch is a pleasant, airy destination, popular with folks who work or live nearby. It may not be just because of the secret sauce, but the smoky mayo is, indeed, memorable (some say addictive), pairing particularly well with a deluxe bacon burger or the Swiss, jack or cheddar cheeseburger. Throw on an extra, like sauteed Portobello mushrooms, and you'll have trouble wrapping your hands -- much less your mouth -- around it. Not a beef eater? No prob. Veggie, chicken and salmon are also available. Milk shakes come in many flavors, but you can hardly beat chocolate for cutting the salt and oil in the fries. Their version's rather like the British ''chip'' -- a deep golden brown, largeish, skin-on, and not crispy, but sweet onion rings (often a previously-frozen afterthought at other burger joints) will make your eyes pop and taste buds salivate. As good as the burgers are, the onion rings alone are worth a visit: one bite and you'll be returning more frequently than once in a ... you know.