I just came back from 10 days in Austria and while at Halstatt we had dinner one evening at Gasthof Zauner and the meal was excellent! Myself and my son ordered the local lake trout grilled (a local favorite) and I can't remember ever having a better entree. The desserts are just as awesome as the main dishes, and the service was great. I recommend anyone going to Halstat to give this restaurant a try.
Don