Toss the sliced chicken with the cornstarch until lightly coated. This is what gives stir-fried chicken that silky exterior and it also helps the sauce cling.
Whisk the soy sauce, rice vinegar, sesame oil, broth, and honey together in a small bowl.
Heat the oil in a large skillet or wok over high heat until it shimmers. Add the chicken in a single layer and let it sit undisturbed for 2 minutes before stirring. Cook until just opaque, about 4 minutes total, then move it to a plate.
Add the asparagus to the hot pan and stir-fry 3 minutes until bright green and still snappy. Add the garlic and ginger and cook 30 seconds.
Return the chicken, pour in the sauce, and toss for 1 to 2 minutes until it thickens and glazes everything. Finish with the sesame seeds.