The food is INCREDIBLE---best in the world! Downtown there are a lot of wine-bars that have awesome appetizer samplings included in the price of a glass of wine, so that's a good way to work up an appetite and then just about every restaurant I've eaten at there has been great; fresh and brilliant.
Heads up on the 'Last Supper'. Don't wear your AC/DC rock T-shirt to go see the painting. It's in a working convent and I was denied access (damn Americans)--it probably doesn't apply this time of year, but no shorts either; (lines can be long; try to get a reservation through your concierge.)