Over the past two or three years, I have probably made over one hundred hashes and, during this time, I have yet to come up with a solution to the problem of degrading fried potato texture in a potato hash.
The challenge is that once the potatoes are crisped, adding vegetables in any form for any period of time immediately softens them.
Here's what I tried (all in concert with one another and on its own): At first I thought I was just crowding the pan so I reduced everything in the skillet so that you could always see the bottom of the pan and thus allow the steam to escape. This did not work. Then I tried cooking everything separately and adding everything back at the end to maintain the texture, but within a minute, the potatoes softened again. I've tried cooking the potatoes at medium low temp to reduce interior moisture, but that process tends to cause some to burn, others to undercook, and those cooked often are hard as rocks with dry interiors.
I'm hoping someone else has experienced this problem and has a solution. I use the serious eats parboil technique with acid at their recommended ratio to maintain the structure integrity of the potatoes during frying so they're cooked before they're crisped.
Is a potential solution here to just absolutely douse the potatoes in oil during the frying process to see if that will provide a more sufficient steam barrier? Anyone have hands on experience with this? I'd like to constrain use of adding additional starches like potato, rice, or panko.