"process how" is correct and usable in written English.
You can use it to talk about the process of how something works. For example: "This article will explain in detail how to process how a computer works."
Process: How would the alternative vote work in practice?
You must have had dark moments during the writing process – how do you cope with these?
What interests me is the process: how do we get from this point to that point?
Specifics of the aging process (how long and at what temperatures) are secret.
He should know what he did — the process, how this process is going to move forward".
The walls illustrate the rum-making process: how stalks of sugar cane are converted into molasses.
I didn't even process how much what I did dictated my personal life".
"But I also wanted to highlight the way and the process how we built the result".
In the absence of a peace process, how concerned are you about a third intifada, or uprising?
This doesn't help us with deciphering a meaning, but it helps us to process how we are looking.
Given how deeply embedded Carruth was in the whole process, how did he know when the film was finally complete?
