Jon Acuff in Quitter has a section about finding a bit of passion for a job that is not your passion. Dan Miller has written before about putting in the hard work at unlikely jobs before you get to where you can really shine. But all, like in Sully, believe in finding your passion.
I think you may not be able to start off following your passion, but you have to not lose sight of it. And we all owe it to ourselves and our current job, to invest some passion into the work we do. Ultimately, you have to take the risk and do what you know, in your heart, you are meant to do.
Maybe it’s just that passion, like people, has to have time to mature. Some take longer than others to mature; other folk seem so wise and confident and capable beyond their years. Things seem easier when we are younger; risks come easier. But it’s not over when you are older; it’s just harder—and harder to ignore. It’s easy to say “Tomorrow” when you are younger; it’s harder to do so when you are middle-aged.
Passion is there. It will change. It will mature. But it has to be found, used, and fed—daily—or you end up missing out.