TheFork users who ate in Chatou have said really good things about Chime Thai, Jaisalmer and Shakti. Maybe you should give them a try!
Some of the more popular Traditional restaurants that offer vegetarian options on their menu in Chatou according to TheFork users include:
Chime Thai, with a 9.4 rating
Jaisalmer, with a 9.2 rating
Shakti, with a 8.4 rating
In those days what better than a traditional restaurant to retrieve the comfort of eating at home.