Since my last post on the elusive perfect home-cooked Kung Pao chicken, I have pursued this grail a half-dozen more times, and I believe I have achieved my goal, or as close as I expect to get in this lifetime.
I started working from a recipe I found here — the photo looked somewhat right, and the ingredient set was close to my preference for a simple chicken, scallion and peanut dish.
I tried out a variety of modifications, including the use of hoisin sauce instead of sugar for the sweetening, but in the end found the simpler white-sugar approach, combined with a switch from light to dark soy sauce, did the trick. I added scallions, eliminated some extra salt, brought the cornstarch level way down (I’ve never been able to put a whole tablespoon of cornstarch into any dish without ending up with muck), and tinkered with the sauce ingredients — adding rice wine and black vinegar. The result is just what I was after. Here’s the full recipe.