Of all the good breadstuffs to be savored around the San Francisco Bay, sourdough is the signature. Some loaves are very sour and pungent and others are more elegantly infused with the tang of their starter; and while I'd be hard-pressed to name the best sourdough in town with certainty -- I like it both ways -- it was a loaf-long epiphany to tear into the one I bought at Acme Bakery. Opened in 1983 by Steve Sullivan, a former Chez Panisse busboy and leading light in defining America's artisan bread sensibility, Acme makes Italian bread, New York rye, cranberry walnut bread, pain de mie, and authoritative pain au levain, its potent sourdough crumb encased in a dark and delicious crust. Pictured above is a simple and perfect sourdough baguette.