On this case: welcome to Southern Germany (soon). We have lots of nature, mountains and beer.

Depending on what your are interested in there may be different things of interest:

• Not that far from Munich is Augsburg, beautiful city with very old buildings. The Fuggerstadt is also very interesting. If you are visiting in August/September you may go to the Plärrer
• You are also pretty close to Legoland which is in Günzburg (buy tickets online and add early as possible, they are usually cheaper then)
• If you go in November there are Christmas markets (the one in Ulm in front of the Münster is kind of impressive though small, Nürnberg is awesome but full) and winter Tollwood in Munich
• Nice seas and hiking locations all around Munich

If you have some more time and maybe want to leave Munich for a few days I’d recommend to either visit the lake of Constance for a few days (Bregenz, Pfänder, Seebühne, … all very impressive and interesting) or go towards Austria and maybe visit Castle Neu Schwanstein (go on a weekday and bring some time with you).

Regarding food I totally agree with the others: look for a nice bakery/cafe and try some bread and cake. Try beers from Augustiner and Chiemseer, Hacker Pschorr is not that good imho.

If you find the time and are interested try to visit the city center on a market day (usually Saturday and maybe Wednesday not sure for Munich).