Unlike the previous poster, I prefer Abyssinia to Dashen, mainly because the atmosphere is a bit nicer, the injera bread is really terrific, and the food has a more stew-like consistency than at Dashen (at Dashen is is a bit too liquidy). It is a bit more expensive than at Dashen, but still quite affordable. A combo platter containing seven or so different dishes is only $11 per person.
As at most Ethiopian restaurants, the food is served atop an injera. I can't remember the Ethiopian names of the dishes, except the Shiro, a spiced chickpea stew that is my favorite and which I often request extra of (you can get extra of one or two dishes free of charge at Abyssinia). Besides the shiro, there is also a spicy lentil dish that is pretty good, collard greens that I enjoy, yellow split peas that are solid, but could be better, a simple dish of potatoes, carrots and green beans which is quite tasty, a salad of tomatoes with onions and chili peppers in a lemon oil dressing that I love, and probably one or two other vegan options that I am forgetting. The food is plentiful, so you will not leave Abyssinia hungry. The server is very friendly but the kitchen can be slow.
Right now, this is the best Ethiopian restaurant in Rochester, in my opinion.