TheFork users who ate in Chamonix-Mont-Blanc have said really good things about Chetif, Bar Edmond and La Trattoria de la Taverne. Maybe you should give them a try!
Some of the more popular Traditional restaurants that offer vegetarian options on their menu in Chamonix-Mont-Blanc according to TheFork users include:
Chetif, with a 6.6 rating
La Trattoria de la Taverne, with a 7.2 rating
Officina del Gusto, with a 7.2 rating
In those days what better than a traditional restaurant to retrieve the comfort of eating at home.