todd–chavez:

Raphael Bob-Waksberg mentioned in this awesome interview(long but worth watching!) that he was browsing through social media and someone noted that what Mr. Peanutbutter made here is a latte, not an Americano. An Americano is espresso with hot water, but if you use hot milk instead of hot water, then it’s a latte. 

And so Raphael was like “shit we need to work out this kink in the show and I need to address that”. So in season three during the flashback, he has Mr. Peanutbutter ordering an Americano, but with steamed milk instead of water. So the joke is that Mr. Peanutbutter doesn’t know the difference between an Americano and a latte which explains why in season two he appears to serve a latte when he says it’s an Americano.