To the anon who asked: Monica first calls Chandler "honey" in 5x12 TOW Chandler's Work Laugh but it's a "fake" honey (it was part of her play to not make Chandler’s boss mad during dinner). Then in 5x23 TO In Vegas, Monica says "it’s ok honey" when Chandler realizes he forgot his present. I may have missed one, I'm not sure :)

$