Prep the chicken: Pat the chicken dry, then slice thinly against the grain. Season lightly with salt and pepper. This helps it sear quickly and stay tender.
Stir together the sauce: In a bowl, whisk soy sauce, broth, oyster sauce, rice vinegar, honey, and sesame oil.
In a separate small bowl, mix the cornstarch with cold water until smooth. Keep both nearby.
Blanch or steam the broccoli (optional but recommended): Bring a pot of water to a boil, add broccoli for 60–90 seconds until bright green, then drain and rinse under cold water. This prevents overcooking later and keeps the color vibrant.
Heat the pan: Set a large skillet or wok over medium-high heat.
Add 1 tablespoon oil. When shimmering, add half the chicken in a single layer. Cook 2–3 minutes per side until just cooked through and lightly browned.
Remove to a plate and repeat with the remaining chicken.
Aromatics in: Add the remaining 1 tablespoon oil to the pan. Toss in garlic and ginger. Stir for 20–30 seconds until fragrant.
Don’t let them burn.
Broccoli time: Add the broccoli to the pan. Stir-fry 1–2 minutes to warm through and pick up flavor. If you skipped blanching, add a splash of water, cover for 1 minute to steam, then uncover.
Combine and sauce: Return chicken to the pan.
Pour in the sauce and bring to a simmer. Give the cornstarch slurry a quick stir and drizzle it in, stirring constantly. The sauce will thicken in 30–60 seconds and coat everything.
Adjust and finish: Taste and adjust with more vinegar for brightness, honey for sweetness, or chili for heat.
Garnish with green onions. Serve hot over rice, quinoa, or cauliflower rice.