I think the part where Tony tells Libby a joke about cookies is funny! I think this, because it was very cheesy, but it related back to them. It related to them, because Tony is not good at baking cookies and Libby is. The joke was...  Where do cookies sleep? They sleep under cookie sheets. Ha ha ha ha ha ha ha, get it? Libby comes back with a joke that says... You know why the cookie went to the doctor, right? Because he was a little nuts. I think that cheesy jokes are funnier that just jokes, that's why I thought that was funny. It also shows their funny relaxed relationship with each other.