Why do we give power and glory and Nobel Prizes to backroom politicos and atomic scientists when we don't even know the name of the genius who first dipped a Hershey bar into a jar of peanut butter? The black velvet of the chocolate, the earthy creaminess of the peanut butter, the salty and the sweet in harmonic convergence ... Madre de Dios! Judy's Candy Company, a Berkeley-based confectioner purist enough to stir its caramels in antique copper kettles over Vulcan burners, truly understands what makes a peanut butter cup great. First, size. Unlike most peanut butter cups, which tease rather than satisfy, Judy's are more than two inches wide. The chocolate itself is dense as a brick, barely sweet and thick enough to make getting to the inner core of peanut butter a real challenge. When you do, it's rich, it's creamy, and it tastes like honest-to-God peanuts, a rarity among peanut butters. You can find these gratifying confections at Chocolate Heaven, a wonderfully fragrant establishment at Pier 39.