When Jack ('Bradley Cooper') is explaining to Mimi about Michel (Michael Vartan), he said, "It's like we worked before." This is an in-joke referring to when Cooper and Vartan worked together on Alias (2001).
Guest-starring actor Michael Vartan as a chef with whom "Jack" Bourdain and his colleagues start a feud. Vartan and Cooper had previously worked together on Alias (2001), and paid homage to this in a character in-joke whereby Bourdain says: "It's like we worked together before or something."