After a bright start from the hosts, Mario Mandzukic put Bayern ahead in the 18th minute.
After two injury-enforced alterations Nuremberg lost their shape and Bayern took control of the game, going close numerous times to making it two before Philipp Lahm sealed victory number 18 of the season on the hour mark.
Nuremberg started well and nearly took the lead in the fourth minute when Hiroshi Kiyotake hit the top of the crossbar with an acrobatic effort.
It was close, like Daniel Ginczek in the first Bavarian derby this season when he also hit the crossbar, but not close enough for a side who have hit the woodwork more than any other in the Bundesliga this season.
Josip Drmic wasted another good chance for Nuremberg with only Manuel Neuer to beat and it seemed inevitable that they would be punished by the runaway league leaders just as soon as they built an attack of their own.
That came in the 18th minute, and Bayern took full advantage with David Alaba's cross volleyed in by Mandzukic.
After losing Timothy Chandler to an injury early on, Nuremberg then lost Ginczek to another injury soon after Mandzukic's goal and Bayern slowly started to gain control of proceedings.
Raphael Schafer prevented Mandzukic from making it two with a diving header after Arjen Robben hit the post and Thomas Muller struck the crossbar with the rebound.
Nuremberg no longer looked capable of finding a way back into the game, and their chances were reduced further when Lahm netted his first Bundesliga goal since December 2010.
Mandzukic unselfishly crossed to his defender-turned-midfielder, who chipped the ball in from close range to restore Bayern's 13-point lead at the top of the Bundesliga.