Yah's is a welcome addition to the south side of Chicago. While I don't think it matches its main competitor, Soul Vegetarian East, it's still good and worth visiting if you are in town.
The space itself is really simple, with about five or six tables that seat four a piece. There's a counter up front and a hotbar showing off the day's food options.
I started with an order of onion rings ($5) which were made fresh. They took a while to arrive (at least 15 minutes) but they were really tasty with a wonderful batter coating. I can't say that they're superior to Soul Veg's onion rings, but these were good in their own right.
I then had the dinner meal of the day ($10) which consists of a large plate with five of the day's options. Yah's also allows you to substitute out certain items for others. In my case, I dropped the grilled broccoli and instead got some mac and cheese (Yah's initially made their fame selling this mac and cheese at a south side farmer's market).
To go dish by dish: the lentil stew was good, but a bit oily. I wasn't a fan of the celery they added to the stew, however. The eggplant lasagna was really good with a creamy, cheesy-topping. The mac and cheese was okay, but not great, in my opinion (my friend thinks this was because it was old and had lost much of its freshness). Next, the stewed sweet potatoes were good but really basic; I would have preferred the BBQ nuggets that the menu suggested they'd give me (but they must have been out of). Lastly, the mushroom patty was excellent: a doughy pastry filled with mushrooms in a sweet wine reduction.
The service was really friendly and helpful but not particularly fast.
I think the main issue I have with Yah's is that the food is not made fresh on the spot. If you get there early in the day, everything probably will taste great; if you come later, and it's been sitting around for a while, it loses much of its appeal. This is why Soul Veg, in my opinion, edges out Yah's (at least for now).
That said, the price for the dinner plate is more than reasonable considering the quantity of food they give you. Sides are $5 a piece, which seems disproportionately expensive, but that's a minor quibble.