Although Barr Tweeted in November that she was "never going work in television again," she returns as a new judge on Last Comic Standing, premiering Thursday.
"I like judging people," Barr, 61, tells PEOPLE of her return to the small screen. "I really like it and thought this would give me the opportunity to tell somebody the truth about something they do. They probably won't listen, but if they do they'll be doing themselves a big favor."
Barr had taken a break from performing or even viewing stand-up comedy, she says from her home in Hawaii.
"I haven't watched stand-up for quite a while," she says. "I guess I got bored with it at a certain point. But I'm seeing and hearing new stuff here that's blowing my mind."
Barr admits that taping Last Comic Standing has rekindled her love of stand-up and caused her to wonder if she might one day give it another go. The Emmy-winner began her career as a comic before going on to produce and star in the hit sitcom Roseanne.
"I'm starting to want to do it again," she says. "But I really don't know if people will want to hear anything I'd have to say. I don't think they could handle it for a second. Once I start going nobody can handle it."
For now, the mom of five seems happy to critique other people's jokes – and to take a little break from her weight loss efforts.
"TONIGHT!: I celebrate my son's graduation from High School and I watch myself on Last Comic Standing! #PizzaANDbeer," she Tweeted Thursday.
Barr and her fellow judges – comedians Keenen Ivory Wayans and Russell Peters – will eventually pick the winner, who will receive a development deal for a TV show.
Last Comic Standing airs Thursdays (9 p.m. ET) on NBC.
TONIGHT!: i celebrate my son's graduation from High School and I watch myself on Last Comic Standing! #PizzaANDbeer— Roseanne Barr (@therealroseanne) May 22, 2014