Finding light, fresh, flavorful and authentic North Indian food at a restaurant is almost impossible, not only in the US, but even in India itself (my parents are from India, and I lived there for over a year as an adult, so I know the food quite well). In India, people expect restaurant food to be heavy and fatty (the healthier stuff you can get at home, so why buy it from a restaurant, or so goes the reasoning), and I think most Indian restaurant owners in the US have that same mentality.
The end result is that 99% of North Indian food in the US is dull, oily and woefully generic (find me a North Indian joint that doesn't have tikka/butter chicken or aloo gobi/mutter paneer and I'll buy you dinner at said establishment).
As such, I had high hopes for Kasa, which sounded like it was aiming for something different. It looks almost like a Chipotle and you stand in line and pick your dishes. To be fair, the food here was pretty good, but my criticisms stem from a lack of variety and some unusual decisions in how they make standard Indian foods (such as dal and roti).
You can get either a kati roll ($4.50 a piece for this flaky tortilla-esque bread, filled with your choice of curry) or a thali plate ($10.50, and comes with rice, two curries and some side salads). Unfortunately, the kati rolls are not vegan (the dough is made with butter); similarly, the roti is not vegan (which is amazing to me, as roti is almost always vegan, whereas naan is usually not).
As such, I opted for the thali plate. Of the five vegetarian curries, only two of them were vegan, which was disappointing. This was sign number one that Kasa is not aiming to offer the simple, light, flavorful Indian food that I dream of.
The only two vegan dishes were the aloo gobi (sigh, how predictable) and an aloo jeera (potatoes and cumin).
To make matters worse, Kasa doesn't offer brown rice. As I hate white rice, and they couldn't give me roti (which is traditionally vegan and made of wholewheat), Kasa did offer to give me more of a curry, so I got an extra heaping of the aloo gobi. That was nice of them.
The food wasn't bad at all. I'd like more variety (two potato dishes is a bit much), and it would be great to have vegan options of dishes that are usually vegan anyway (such as dal), but the food here was about as light and simple as I've found in the US.
If they had more vegan options for curries, and offered vegan breads (they said they can make vegan bread with advance notice, but it takes them about 40 minutes or more to make the stuff), as well as homemade chai with almond or coconut milk, Kasa would get another star. For the price, too, it's not a bad deal, as you get a pretty filling meal. Kasa has much room for improvement, but if you're looking for decent Indian food in the Mission, this is your spot.