Medl Brau brews an awesome beer in Vienna. Besides the good beer, they have a big offer of typical Austrian food and some seasonal menus! In summer you can use the garden. Mostly Austrians there, they speak little English. The brewery is close to where Gustav Klint was born, a bit on the outsides of Vienna.
The place has different kinds of Austrian beers (Märzen, Helles, Dunkles), some of them unfiltered, and the bock in special occasions. The environment is also cozy, full of wood and the typical Austrian benches in the dining table. You can check their whole menu on the webpage http://medl-braeu.gusti.at/index.php
In winter they are just open from Tuesday to Saturdays from 10 am to 10h30pm (for the beer, you can arrive later).
Tu-Sa: 10:00-00:00