TheFork users who ate in Fontainebleau have said really good things about Ma Su, Le Tendance and Le Franklin. Maybe you should give them a try!
Some of the more popular vegetarian dishes restaurants to eat on budget in Fontainebleau according to TheFork users include:
Le Tendance, with a 8.8 rating
Le Bella Sera, with a 7.7 rating
The Dish, with a 7.8 rating