When I want Ethiopian food, which happens often, I always go to Ras Dashen. The food is delicious—the best Ethiopian I've had—and the staff is always friendly and helpful. Sometimes, when they are trying out new vegan dishes, they'll bring us free samples and ask our opinion.
My favorite dishes are the shirro and the mushroom wat. The latter is not on the menu, but they have had it every time I've asked.
They also offer Temptation vegan ice cream for dessert, though I have yet to have room for it when I'm done eating.