I realized that this was my dream job not because I didn’t think I could ever do it, but because I actually knew I could.

When I was transitioning from a career as a magazine writer to a TV writer in the late 1980s, I had one dream: to write for Late Night with David Letterman. The show was quirky and irreverent and I thought I could capture its sensibility. I asked my agent about getting hired on staff and he told me it was a long shot. In seven years, the show had only hired one female writer (who was also Dave’s girlfriend). It was a boys’ club—as most late night shows were and still are. I was told I would be wasting my time to even try.

But I was young and had nothing but time, so one weekend I sat down and generated pages of jokes and ideas for the show. I didn’t know how to officially apply, but I had the name of the head writer so I sent him the material. I felt confident I would get a response.

I heard nothing back.

But my agent sent the material to another variety show and they hired me off those jokes. That job led to another gig as a writer on the final season of the sitcom Newhart. My TV career had launched, in part, thanks to the work I’d done for a show that never responded.

Still, the dream of writing for Letterman didn’t go away. And as Newhart was winding down, I decided to again submit material. I even included a little Japanese toy I thought might catch the head writer’s eye. I felt confident that at least the little toy would get a response.

I heard nothing back.

In the meantime, I received an offer to work on another sitcom. It wasn’t my dream job, but it was a good one. After I’d been working on the show about a month, I received a phone call. It was the Letterman head writer who had showed my material to Dave. He liked it. Would I come in for a meeting?

I was overwhelmed with excitement. Except I had a problem: I already had a job with a two-year contract. I decided to approach the show’s executive producers—a married couple—and be completely honest. If I was offered a job, could I take it? They could not have been nicer and it helped that they were Letterman fans.

I flew to NY and met with Dave. Waiting to enter his office, I felt scared and nervous. So much was riding on what happened next, and yet once I walked in to greet Dave, the nervousness went away. I saw the pencils stuck on the ceiling, the gap-toothed smile, and it felt familiar, not uncomfortable. I realized that this was my dream job not because I didn’t think I could ever do it, but because I actually knew I could.

The meeting was short. Dave and I talked about living in Los Angeles versus living in New York. We talked sports. I didn’t freak out or make any sudden moves. Later that day, the head writer phoned to offer me a spot on the writing staff.

My dream came true thanks to persistence, and an eye-catching toy. I can still remember walking to work on that first day, and the pride I felt as I entered 30 Rock to be a comedy writer. Liz Lemon knows what I’m talking about.

And I’ll never forget my first joke that ever aired on the show. The Top Ten List that Monday night was “Top Ten Least Popular Summer Camps.” My contribution just snuck in at number 10: “Camp Tick in beautiful Lyme, Connecticut.”