LORELAI: Oh, well, I brought pizza if you guys are hungry.
In previous seasons, Paris is said to be lactose intolerant, and cannot eat cheese. When she had pizza before at the Gilmores’, Lorelai got her a pizza without cheese on it. This can’t be the case now, as Lorelai didn’t know Paris was coming over. Maybe the big blow out of mac and cheese Paris had when Jess brought dinner over taught her that she wasn’t as lactose intolerant as she thought?
The Annotated Gilmore Girls 