Chez Paris is a French restaurant located in Hillwood, located next to Chez Pierre.
It is here in Arnold's Valentine that Helga, pretending to be Cecile (Arnold's French penpal), was having a meal with Arnold while taking shifts in having a meal with Ruth over at Chez Pierre. Not understanding French herself, Helga ended up ordering cow brains and eggs, which caused her to throw up in the bathroom.
In Dinner for Four, Helga won a coupon for a free meal in Chez Pierre. She decided to invite Arnold, Gerald and Phoebe to the meal, but once it came to paying the bill, it turned out that they were in Chez Paris and not Chez Pierre. This leads Helga to stall the waiter until Nadine arrives with her box of bugs so to escape. When Arnold discovers what Helga did, he convinces her and the others to go back to the restaurant and admit the truth to the staff, which leads to the four of them being forced to wash dishes to make up for what their meal was worth.