To a large bowl or gallon sized ziptop bag, add the chicken, 3 tablespoons cornstarch, and toss the chicken in the cornstarch in the bowl (or seal the bag and shake vigorously to coat evenly). Tip: Cornstarch helps the exterior of the chicken get lightly crispy without frying it, and shouldn't be omitted.
To a large skillet, add the olive oil, chicken, and sauté over medium-high heat for about 5 minutes, or until chicken is cooked through and done. Stir and flip frequently to ensure even cooking. When the chicken is done, remove it using a slotted spoon and set it on a plate momentarily. Tip: Want to use boneless skinless chicken thighs? That's fine, they'll likely need an extra 1-2 minutes to cook through.
To the same skillet (don't wipe it out), add the garlic, ginger, and if necessary add a bit more oil if your skillet is dry, and sauté for about 1 minute; stir constantly so garlic doesn't burn.
Add the soy sauce, honey, broth, sesame oil, and whisk to combine. Set aside momentarily.
To a small bowl, add the remaining 1 tablespoon cornstarch, 1 tablespoon water, and stir to combine and dissolve the cornstarch. This is called a slurry.
Add the slurry to the skillet with the other liquids, and whisk to combine. Cook for about 2 to 3 minutes, whisking nearly constantly, until sauce thickens slightly. Tip: Cornstarch is essential because it helps the sauce thicken and can't be skipped or your sauce will be thinner and won't cling to the chicken. Sauces always seem thinner when they're in the pot, with the stove on, so it won't get overly thick, but thicker.
Add the chicken into the sauce, stir to combine and coat evenly. Taste and if desired, add salt and black pepper, to taste. Flavoring Tips: Depending on the brand of soy sauce and broth you use, and your personal preference for salt, you may or may not need to add salt.
Optionally garnish with green onions and/or sesame seeds, as desired, and serve immediately (with rice, quinoa, or something else to soak up the sauce is recommended).
Storage: Extra chicken will keep airtight in the fridge for up to 5 days or in the freezer for up to 3 months. Reheat leftovers in the microwave for about 30-60 seconds, or as needed.
