Wandering Adventure Party

A sauce will usually be a liquid with a thickener added. Chicken broth plus flour would give you gravy like for roasted chicken. Chicken broth plus corn starch would give the same flavor with a different texture, like something from Chinese take out. For a thick weak soy sauce, you could mix the amount of soy sauce you want for flavor with the amount of water you want for volume. Mix in some corn starch and heat it up. I don’t know how good that would be, but I think it would get you what you are looking for, and you can experiment from that point.