On the plus side, a Kölsch recipe is about as simple as you can imagine (see below for a starter recipe). You just need pale two-row or pilsner malt to hit a starting gravity of 1.045–1.050, a couple of additions of Noble German hops to get 18–24 IBUs, and a top fermenting Kölsch yeast.
The current Beer Judge Certification Program style guidelines correctly indicate that this is rare in authentic Kölsch. A small portion of wheat malt is OK; the same as adding Vienna malt. Wheat can add a gentle bready note to the beer and can improve head retention. Overall, try to keep it simple.
Kölsch is best served fresh and around cellar temperature. If you can serve your Kölsch in a tall, narrow, straight-sided glass, it will also make a difference in your perception of the beer. The all-grain version of this recipe uses a small amount of Vienna malt.
German noble hops are the hops or choice with a good Kölsch. Hallertau, Tettnang, Spalt. Some brewers like Willamette, Liberty, and Fuggles. Stay away from the American citrusy hops. Transcript: Enter Martin Keen – The Homebrew Challenge to brew 99 beers styles in 99 weeks.