"King Size Homer" - the one where Homer gains enough weight to go on disability.
Classic episode.
"Oh no! The corn! Paul Newman's gonna have ma' legs broke."
"I don't want to look stupid, I'll just go with the Moomoo."

This is my favorite. 2nd is the Gummi Venus De Milo episode...
Homer Bad Man She was a university honor student who devoted her life to kids,
[slomo of Homer reaching for his car keys]
until the night a grossly-overweight pervert named Homer Simpson
gave her a crash course in depravity. "Babysitter and the
Beast"!
-- The "Rock Bottom" show, "Homer Bad Man"
"Aw, crap," laments Homer as the interview is shown.
Homer: Somebody had to take the babysitter home. Then I noticed she was
sitting on [splice] her sweet [splice] can. [splice] -- o I grab
her -- [splice] sweet can. [splice] Oh, just thinking about
[splice] her [splice] can [splice] I just wish I had he --
[splice] sweet [splice] sweet [splice] s-s-sweet [splice] can.