A two-day festival celebrating chocolate? Sweet. Ghirardelli Square’s 13th annual Chocolate Festival (September 6–7) will feature wine-and-chocolate pairing seminars, cocoa tastings, a cupcake-frosting demonstration from Kara’s Cupcakes and much more (noon–5 PM; 900 North Point St.; attendance is free, though tickets are required to participate in various tastings; see more details).