Homemade loco moco + gravy options?

Been having a major craving for loco moco lately but I couldn't find specific gravy for it, knowing it exists. I'm wondering who here makes it and if they just use standard beef or pork gravy? I ended up buying this from Amazon, which unfortunately comes in a 12 pack but it'll last until 2028 or something crazy which is good.

So I whipped it up, but added some red pepper flakes and dashes of Tabasco sauce as I kinda like mine leaning spicy ala Ventiki. I think it made a dramatic improvement, and aside from needing to work on the burger patty (just seasoned w/salt and pepper, but cooked on the stovetop which dried it out) I thought it was pretty excellent. A bit of an effort considering I have to do 4 things separately, but I'm a tad proud of myself for finally getting up to do it.