Once charges are preferred you will get an appointment with TDS on post. They will discuss with you a Chapter 10 in lieu of trial by court-martial.
That written request is forwarded by your commander to the general officer/general court-martial convening authority for your post, who will approve/deny.
If approved then you will be separated with an OTH.
Whether or not it is approved will depend on several factors: length of absence, surrendered or arrested, quality of service before the AWOL, can they prove desertion, and the reasons why you left, and whether or not there were other charges pending when you went AWOL. It is helpful that your current commander is not aggravated with you.
I'm not aware of the statistics for Fort Hood, so not sure of the likelihood of success. Perhaps another of the commenters know.
There is a good informational pamphlet available at the web address below that explains the process and consequences.