Good cooking question — answering as the UphillTech team:
Many restaurants actually serve a "light" version of the Tso sauce, and I have a pretty strong feeling that's what you're used to. To make the light version, you use 3x the corn starch and add 1/2 cup of the base liquid (usually chicken broth). The hint of sesame almost certainly came from toasted sesame oil, my favourite "secret ingredient" that goes into just about every Asian stir-fry. To get a more consistent flavour for the sauce, instead of using "minced" garlic, you might want to grate it using a fine rasp, if you have one. This will definitely help to bring out the flavour of the...
Full answer by Aaronut: https://cooking.stackexchange.com/a/3088 (CC BY-SA 3.0).
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