Prašná Bašta was recommended to us by our hotel. We only asked for somewhere that we could get "a quick bite", and were pleasantly surprised by what we found.
The food and service were great, the staff were helpful and spoke English, and the prices were very reasonable. We ended up going back the next day for more.
I would thoroughly recommend Prašná Bašta! I've given this restaurant five stars on all levels. While I don't think this is a 3-star Michelin restaurant, I think it deserves a very high rating considering the price, quality, location and service.