[dmtaylor]

If you're looking for the pale yellow festbier, this should get you into the right neighborhood, for 5 gallons or 19 litres:

7 lb German Pilsner malt
3 lb German Munich malt
1 oz Hallertau Tradition (45 minutes)
Wyeast 2206 (accept no substitutes)

Make a big 3-quart yeast starter a few days in advance.
Single infusion mash in 100% distilled water about 149 °F for 120 minutes or overnight.  Pitch and ferment at 50 F for 6 to 8 days, then raise up to 65 F for several days or until diacetyl is gone.  Then lager if desired, bottle or keg as normal.  Might improve after 4-5 months lagering in the bottle/keg.

I like some Vienna in there too. I basically brew a strong helles, which usually has either a little bit of munich or vienna, but for Festbier, I include both.

I like Vienna as well; HOWEVER, I was basing this recipe directly on what Paulaner provides for the recipe on their web page.  They don't actually use any Vienna.  Doesn't mean we can't, but... it's a clone attempt, so...

[Saccharomyces]

Most of what American craft brewers make is "American Märzen."  That stuff is just sickly-sweet disgustingness in my book.  It is a holdover from the early days of craft brewing when everything was made using American 2-row malt and too much crystal malt.   It tastes nothing like a true German Märzen or Festbier.