If you want authentic Austrian food in Salzburg, head to s’Herzl on Getreidegasse, the main shopping street. At first, one appears to have entered an Epcot dining experience — the small dining room is wood-paneled and suitably medieval, and the waitstaff wear the classic Austrian dirndl.
Fortunately, the food is more than solid, and one is not subjected to the best hits from The Sound of Music. (That movie, by the way, is about as culturally accurate as, say, the portrait of small-town Iowa in The Music Man.) The go-to dishes are the Weisswurst with large soft pretzels, served with Senf, a slightly sweet mustard; or the Gemischter Salat, which is a mix of grated carrots, greens, and cucumber with dill, and first-rate Austrian potato salad.