Known primarily for its perfection of the carrot cake, Marty's Baking has, in the past year or so, exploded into one of downtown's most popular hidden treasures for lunch and Sunday brunch. This out-of-the-way spot, near Lafayette Square, has been the destination of many who agree it's well worth the drive. That's because every single menu item is 100 percent homemade in a kitchen that is clean and wide open for everyone to see. From Marty's curried-chicken salad to assorted wraps, daily specials, soups and the cake-packed pastry counter, the price may be slightly higher, but, then again, so are the standards. The laid-back mood of Marty's interior design is sort of San Francisco-bistro-meets-Seattle-coffeehouse-in-Greenwich Village.