Maybe you were thinking fruit -- or possibly (gasp!) veggies -- would mar the area's best beet cake. Fear not. The beets are there, but you really can't taste them in the tavern's moist, brownie-esque chocolate sweet. At Jimmy O'Neill's, the huge slice you get for five bucks comes covered in melted Belgian chocolate, a decadence that begs for a glass of milk to wash it down. It's topped with whipped cream so light and fresh, it looks like sweet butter melting on the mound of chocolate. This is the kind of dessert that must be shared -- or at least gloated about -- with friends.