There are so many reasons to go to Tosca — the hearty Italian fare from April Bloomfield, the masterful cocktail list and the extensive selection of Italian wines being some very good ones. But the real reason to go to Tosca is to soak in its marvelous, booze-soaked history as being the place for the artists and poets and everyone else who mattered in San Francisco. When you sit at the bar, you'll see that it still is. And now, you can get guanciale meatballs, too.