Back in September 2007, a 21-year-old Cuoco made her debut as Penny in the comedy sitcom's pilot episode, following her role as Bridget Hennessy on 8 Simple Rules. While giving ET a tour of the Big Bang set that same year, Cuoco revealed that she originally didn't get the part as Penny from producer Chuck Lorre.
"This show, for me, has been circulating for so long," Cuoco, now 33, said at the time. "I actually read for it two years ago when they had done it and didn't get the job. Chuck was like, 'You're just too young.' I was like, 'OK,' and went away. Then I heard they were reshooting and I'm like, 'Mmm, mmhmm.' Then I got the call, they're like, 'Do you want to come back in? We're still interested in you.'"
"I came in, I got the job and it got picked up and it was, like, this whirlwind," she recalled. "It was awesome."
Cuoco added at the time that she felt like she shared quite a few similarities with Penny. "She's just so loud and basically like me," she said of her character. "She's all over the place and [the guys] just don't get her. So, it's going to take some time to kind of, you know, become friends first."
It appears that Cuoco had no problem making her own real-life friends on set, however. Since the beginning, the blonde beauty has always been raving about her co-stars, like Jim Parsons, who plays Sheldon Cooper. "[He] is my idol," she gushed to ET during our 2007 set visit. "He's so hilarious. This man is so funny. He'll read his lines, I'll go, 'Jim, did you study this weekend?' He's the studier. I just love him. He's a genius, honestly."
Over a decade later, Cuoco, Parsons and the rest of the close-knit Big Bang cast are gearing up to say goodbye to the beloved set that ET returned to 15 more times since that first visit. The series wraps its 12th and final season this week, and while it's certainly bittersweet for everyone involved, the cast and crew are just happy to have made memories that will last a lifetime.
Looking back on all those years on set, Cuoco recently told ET that she loved that so many people were involved over the course of 12 seasons. "There's so many different people and families. It just goes so deep and so many people are connected to this show and so many fans," she said. "It's created its own little world."
Cuoco revealed that she was also "thrilled" when she learned how Penny's story wraps up in the upcoming two-part finale. "This has been a stress for months [for] us actors, and the writers -- how's this gonna end?" she explained. "This is my legacy of this character, on and on. I'm thrilled with [Penny's] ending, yet beginning. It's beautiful. There's not anything catastrophic, it's just beautiful."
"The characters are gonna live on in your minds and in your hearts, and I think that's what is so special about it. It's really touching," she continued. "It is the most beautiful finale I have ever seen, and I love finales. You're gonna cry, but in the sweetest way. I don't know how to describe it, other than it's absolutely the sweetest thing in the world."
Still, Cuoco is not exactly ready for the series to end. She joked to ET last November that life after Big Bang will never be the same.
"It's something I'll have for the rest of my life. It's something I'll probably compare every project to, like nothing will be like Big Bang," she said. "It just is what it is. It's made me who I am. It's given me so many great things and blessings and I'll be very indebted to the show and Chuck Lorre forever."
As for how she plans to spend her time next? It's simple: "I think a lot of horses, apparently a lot of pigs, a lot of bunnies. And being home with my husband [Karl Cook]. I'm excited about that."
The two-partseries finale kicks off Thursday, May 16. In the meantime, hear more from the cast in the video below.