Following a fellow Chowhound's suggestion, I threw down $2.25 for a cup of hot chocolate at Cafe Madeleine on O'Farrell/Market.
WOW, that was worth it: I don't think I'll ever be able to drink hot chocolate out of a paper pouch again. Honestly, I did not know hot chocolate could taste like that. The hot chocolate is made with a semi-sweet, dark chocolate-like ganache. It's topped with frothy steamed milk. The result is a thick, creamy, piping hot drink of a consistency somewhere between that of latte and egg nog. Chocolate whipped cream is optional.
I had been freezing my fingers and ears off in my office all day, but was warm for the rest of the afternoon after this meal of a drink.
BEWARE: of you are lactose intolerant or dislike creamy things, you'll probably want to stay away from this particular slice of Heaven.