Sogem has a quiet, pleasant atmosphere and pretty good food. There are always a couple set meal options for vegans. The food is prepared and presented in a traditional Japanese style. It's not usually highly flavorful, but is somewhat tasty and is healthy. Typical set meal includes brown rice, miso soup, a small entree, and several side dishes and tea. Price is reasonable.
Sogem is in a residential neighborhood a 20 minute walk from downtown and might be a little hard to find. It's at an intersection and is probably most easily identified by the attached natural foods/products shop which has much more obvious signage than the restaurant, whose door is around the corner from the shop.
I've been the only one in the restaurant nearly all of the half-dozen times I've been there.
Sogem recently switched to a by-appointment-only system for dining so you need to call in advance or there will be no food for you.
Often there have been no English speaking staff when I've visited.Pros: traditional Japanese vegetarian food, quiet, pleasant atmosphere, no competition for seating
Cons: appointment-only dining, a bit out of the way, usually no English spoken