For 100 pounds of grain, depending on the strength of the beer, between 600 and 700 pounds of water are used.
The crushed grain is put into the mash tun dry. As soon as the water in the kettle has boiled, cold water is added to cool it down to 82.5 - 87.5º C. The water is then mixed with the grains. This shouldn't occur too quickly, so that the temperature of the grain rises slowly. This is important as all 600-700 pounds of water are used at this first mash. The temperature after all the water has been added should be 62.5º C.
After a short rest, the first wort is transferred to the kettle and boiled for 45 minutes. This Lautermeisch is put mack into the tun and the temperature of the whole mash should then be 75º C. After mashing well, the mixture is left to rest for an hour. After this the finished wort is drawn off.
In Franconia, very frequently the hops are boiled for half an hour with a small quantity of the first wort to be drawn off. This gives the beer their distinctive taste. It's called "Rösten" the hops.
Cold water is poured over the spent grains to remove the remaining extract. In the Bamberg area this wort is called Hansla and is used to make a weak beer. In volume, this is almost half the amount of the full-strength beer.
I hadn't expected them to have used a single decoction like this in Franconia. My guess would have been triple decoction.
Still not quite done with Bavaria. There's also the Kulmbach method.