I had dinner at the Aux Deux Portes Cafe on Tuesday last week. I went there with a non-vegetarian friend and we were both satisfied at the end. I had a quinoa salad and beetrot & carrot as a side, plus a delicious slice of tofu and berries cake (and a glass of water).
Prices were ok, being this place in Geneva: 10 CHF the main dish, 5 CHF the side, and 5,50 CHF the cake. Portions are by no means big, but the food was nice and spicy.
The lady was kind, but she didn't speak English. I had to use my terrible French and in the end it worked out fine (a customer actually offered to translate for me, but the lady said: "let him try with French"... :--).
I give this place 5 happy cows: it's so hard to find vegan stuff in Geneva (and Lausanne is the same), that it was a real pleasure eating there!
Cons: You need to speak French a bit