I have gone through four different internet recipes on this, and they all suck and taste nothing like the yummy goodness of sesame chicken from take out.
Anyone make a good version of this? I am dying to know. 
Most recipes online will be for home-style cooking, not necessarily to imitate takeout-style. The “secret” for chinese restaurant-like chicken, at least from a textural standpoint, is the cover the bits of chicken in corn starch before frying in oil. Even if it’s a non-breaded chicken, or even if it’s beef, that makes all the difference.
To me, sesame chicken means something battered in a thick sauce. The breading would probably be corn starch, milk, and egg.
Remember that chinese takeout places are like factories, considering how much food they pump out in a day. They only use a handful of ingredients, just arranged differently. Play around with different variations of corn starch/egg/milk (and white pepper) to find a batter mixture that’s right for you.
As for the sauce… I don’t usually make glazes, so it’d be bottled for me.