Try this General Tsos Chicken recipe, or contribute your own.
A list of ingredients fails to reveal how physics dictates textural survival in a wok. Starch chemistry rules the batter phase. When cornstarch hydrates with egg and water, it forms a dense, viscous suspension rather than a runny pancake-style coating. That putty-like consistency insulates the chicken muscle fibers, preventing rapid moisture loss while water molecules flash-boil and escape through the starch matrix. This creates microscopic pockets of air, resulting in a shatteringly crisp crust.
Maintaining that crunch requires strict thermal control. Oil heated to 350 degrees Fahrenheit instantly vaporizes surface moisture on the batter, setting the starch structure before the fat can penetrate the interior. Overcrowding the pan causes oil temperatures to plummet below 325 degrees, leading to soggy, oil-logged coatings because the moisture cannot escape fast enough to prevent saturation.
Sauce application is a race against thermodynamics. Pouring the liquid mixture over the hot fried chicken initiates rapid starch gelatinization. Pectin and cornstarch in the sauce thicken rapidly under medium heat, locking the glaze onto the exterior without dissolving the fragile starch crust underneath. Speed is mandatory here. The chicken must enter and exit the bubbling sauce within thirty seconds, or residual steam migrating from the interior will soften the outer shell.
Leftovers present a structural paradox. Reheating moisture-laden fried proteins in a microwave destroys the crust entirely, as steam trapped inside turns the starch back into gel. Instead, revive chilled portions in a 400-degree oven for six minutes to drive off surface condensation and restore crispness.