Cee Lo Green has worked with plenty of professional musicians and he knows a thing or two about recording hit songs. But the Gnarls Barkley frontman and solo star said even he was impressed with the vocal skills he heard on Monday when "Country Strong" actress Gwyneth Paltrow joined him in a New York studio to record a new version of his Grammy-nominated smash, "F--- You."

"We already went into the studio together to record a special rendition of 'Forget You,' " he said on Wednesday of the sanitized version of his viral hit. "I started off the new year [in] a very special way and that's recording with Miss Gwyneth."

The Lady Killer singer had nothing but kind things to say about the budding recording star, describing her as "very pleasant," "very pretty" and a "consummate professional." After some small talk to break the ice during their first meeting, Cee Lo said he shared some laughs with Paltrow before they got down to the work at hand. Ever the gentleman, he let the lady go first and, well, she killed it.

"In about four takes, impressively, she nailed it," he said, noting that Paltrow was very familiar with the song thanks to the clean rendition she did of it for "Glee" in November, which he highly praised at the time. With the song's producers, the Bruno Mars-led Smeezingtons, on hand to handle the remake, Cee Lo said there initially was a concern about the actress being able to sing in the Goodie Mob member's range. "She got in and she sang the original key the song was recorded in, so there wasn't much we had to change," he maintained.

The Smeezingtons are working on remixing and remastering the session as we speak. Cee Lo hasn't heard the final version yet, but he's hoping to be pleasantly surprised by the finished product. While the track was originally recorded for one voice, he said they were able to turn it into a duet by going "back and forth and [doing] our little Sonny & Cher kind of thing."

Paltrow has reported that she watched hours of performances by her pal Beyoncé, as well as footage of Michael Jackson, to get her vocals up to snuff for "Country Strong," and Cee Lo said the hard work clearly paid off. "To hear her sing in person, it was cool," he said.

"I was impressed. She's got great vocal control and range ... she did her warm-ups and her ritual ... I don't really do any of these things. I just roll out of bed and just sing. She was very professional and very clear ... it was great. It was a cool experience."

Cee Lo added that Paltrow was so on the mark that she knocked out her main vocal parts in about an hour, requiring just a handful of takes to get it right. At this point, it's unclear if the song will be formally released as a single, but Cee Lo plans to send it out in the world to allow people to appreciate it as a "conversation piece."

"I'm not sure if it will be released to iTunes ... I'm not sure of the long view and plan for it," he explained. "She was up for it and, of course, I was like 'great.' It gives me an opportunity to meet her and do something. We're just all in the moment right now."

Considering that Cee Lo will be the musical guest on the January 15 episode of "Saturday Night Live," which Paltrow is hosting, the R&B singer said you can be "certain" that there will be a musical meeting of the minds on the show. He was coy about whether they'd debut the "F--- You" duet that night, but with both of them in the house, anything is possible. "You can assume that," he said when asked if they'd sing something together on the show.

Are you excited for the "F--- You" duet? Let us know in the comments!