Ask HN: Can you recover from burnout without switching jobs?

I've been at my employer (unicorn startup) for several years now, and have worked myself to a staff+ role. I burned out pretty badly last year. I've been slowly coming back from that: a moderate workload, better separation between work and not-work hours, etc. I'm better now, but the enthusiasm/enjoyment I had before is totally gone, replaced with a knee-jerk cynicism/fatalism that I don't really like. All of my personal expectations for performance are also anchored at what I did at an unsustainable pace, which makes it hard to feel good about what I'm contributing now (I still get decent reviews even if I'm not a star performer anymore).

Separately, I feel like I'm in a rut. I've done more or less the same thing for a couple years now, and I've done all the growing I'm going to in that function. I'm aware of other opportunities within the org, but the lingering burnout/cynicism/fatalism make it hard to get excited about them.

My first reaction is to take a couple months as a breather, and get a fresh start at a new job; leaving baggage behind, hopefully not working myself to burnout again. Aside from burnout, I do really like my company, though – the people are fun, the product is interesting, the pay is good, etc. If I could confidently address the issues above without leaving, I would.

I'm curious if anyone has managed to turn around a situation like this without getting a new job. What did you do? If you switched projects/roles within the same company, was that enough of a reset? Did you end up staying for a while afterwards, or were you gone anyway in short order?