Something to try
You can get either a large bottle or smaller samplers of things like Everclear and Old Smoky
Then, experiment soaking with oak chips of varying char
After about 6 weeks you can start tasting to see how they are doing
Aim for or dilute to about 110-120 proof for this process
I'm becoming dissatisfied with most bourbons lately and so I've taken up the challenge to produce something I like.
The process this way is faster than you might imagine and 90-95% as good as you can get the multi-year way ( on a good year, good oak )
It is rewarding to observe/taste the evolutions over time.
And boy do they evolve, harsh one time, mild the next, more firey this day, mellowed out a few days later, etc., etc.,