For Foo Fighters frontman Dave Grohl, working with music legend Paul McCartney was quite a smooth ride.

It was so smooth, in fact, that it only took them three hours to write and record 'Cut Me Some Slack,' the gritty track they played at the 12-12-12 benefit for Hurricane Sandy. That performance was hailed as a McCartney-fronted Nirvana reunion, since Pat Smear and Krist Novoselic also performed. It was such an easy process because they elected to do things the old-fashioned way.

Grohl also gushed about how rad McCartney is, deeming him "just the sweetest, nicest, most awesome person" in an interview with KROQ (quotes via

If you need another reason to see Grohl's directorial debut, 'Sound City,' a documentary about the famed recording complex in California, well, he's got one for you. He and McCartney recorded some performances for the film. That's how the conversation about working together again came about, and how 'Cut Me Some Slack,' which they also performed on 'SNL' before the holidays, was born.

"We walked in; we jammed the song," Grohl said. "It just came out of nowhere. The best songs happen that way. We recorded it live and put a vocal over it and that was it. It was three hours and it was perfect."

It appears that the rock icons from two different eras and generations decided not overthink things and just go with it. They also employed a "classic" way of making music -- artists getting together, playing and reacting to one another's chemistry, as opposed to getting bogged down by too many opinions, songwriters and studio equipment.

He continued, "You have to understand, one of the great things about playing with Paul McCartney or playing with Neil Young is that that generation of musicians, they cherish and respect and value the practice of just going into a room and coming up with something and jamming and making it a song."

"There’s not like seven songwriters and seven producers and digital technology or whatever," he added. "It’s like people getting in a room."

It may be a "quaint" way of doing things, but you can't argue with the result.