Caffè Rivoire (address and info)
"Rivoire in Firenze is the only place for the Negroni, because it's where Luca Picchi works. He wrote a beautiful book about Count Negroni called Sulle tracce del Conte, and he makes the ultimate Negroni. It's served in a giant bucket glass with ice and a slice of orange, which is how it should always be served. We grew up drinking soda pop in America, so when we drink something like Campari we don't like the bitterness. When a drink warms up, the bitterness is multiplied, but if you put it on the rocks, the best sip is the last sip."