Thank Goodness You're Here!

Any time you are in the first area, head over to the Thumbitt Inn. Break all the glasses as you go along. You need to visit the pub five times throughout the game before Larry will list his favorite drink. This will only count if you trigger new dialogue from him, so you can't just walk in and out multiple times. You have to make some progress in the story first before you can come back and talk to him again.