I noticed that David Chang likes to add a bit of agave nectar to his fried rice. I never thought about adding something sweet to this, so I started adding a small amount of brown sugar (maybe 1/4 to 1/2 tsp) to my fried rice, and it really seems to make it tastier. It doesn’t read as “sweet” - it just gives it a tiny bit of an additional flavor boost. Since then I’ve also tried playing around with adding a tiny amount of sugar to other things, and it’s usually pretty good.
Oh, yes! And sugar, and acid. So good when cooked down and concentrated.