I always order the vegetarian (VGML).
There are a few in rotation right now; I usually end up with either the chickpeas in tomato sauce or the diced potato, spinach, and peas. The latter is fairly bland, but I really like the chickpeas. Both come with a side of rice, a shrink-wrapped dinner roll with dairy free margarine, and a fruit salad for desert.
For breakfast, the VGML is generally a fruit platter, but on a few occasions I have been served a scrambled tofu dish which was quite good.
On shorter flights, where the cheese plate is served, I've had a roasted vegetable sandwich (not the one from the back, which has mayo on it and is not vegan).