You haven't said what type of food you're looking for but if you want the real deal local German food that is uniformly excellent, then I'd recommend Gasthaus Gottfried in Kreuth which is really close to Tegernsee which is really pretty. I've been going there for over 15 years and have never been disappointed. This would be approx one hour from the Welt on the Autobahn direction Salzburg. If you have navigation, it would be helpful.
http://www.kreuth.info/goettfried/