Reddit reviews A Taste of Aloha: A Collection of Recipes from the Junior League of Honolulu

My basic teriyaki sauce is definitely just shoyu and sugar. If you're looking to do more gravy-ish, make a tiny amount of roux, and then mix it in, maybe with some water if it gets too thick.

My personal katsu sauce is ketchup, shoyu, worcestershire sauce, brown sugar, and a dash of sriracha sauce (or whatever your preferred hot sauce). I don't know measurements since I just do it to taste - just add a bit at a time of everything until it tastes right. It's not quite as good as some of the commercial ones I've had, but it works for me.

In all reality, though, see if you can find anyone who will mail you some of the local "fundraiser" type cookbooks. You know, the ones schools and sports groups compile every few years to fundraise for a tournament or whatever. Almost all of those have at least a few winners in the "local food" category like shoyu chicken and sushi rice. I personally remember the Central Union Preschool cookbook (but that was when I was in preschool which was... a long time ago), the Honolulu Waldorf School cookbook... Oh, not a fundraiser, but "Taste of Aloha" - I think there are at least two volumes. You'll appreciate that one, I'm pretty sure. Looks like there are some good choices on the Amazon vendors thing although Amazon proper doesn't sell it. Dude. Now that I think about it, you MUST buy it. There are so many good recipes in there.