Prep the chicken and veggies: Pat chicken dry and cut into pieces. Slice onion and bell pepper, and prep broccoli and snap peas. Mince garlic and grate ginger.
Make the sauce: In a small bowl, whisk soy sauce, water, honey, rice vinegar, sesame oil, and sriracha if using.
Set the cornstarch slurry aside separately.
Sear the chicken: Heat oil in a large skillet over medium-high. Add chicken in a single layer and cook 4–6 minutes, stirring once or twice, until just cooked through and lightly browned. Remove to a plate.
Stir-fry the veggies: In the same skillet, add onion and bell pepper.
Cook 2 minutes. Add broccoli and snap peas with a splash of water, and steam-sauté 3–4 minutes until crisp-tender.
Add aromatics: Push veggies to the sides. Add garlic and ginger to the center and cook 30 seconds until fragrant.
Combine and sauce: Return chicken to the pan.
Pour in the teriyaki sauce (without the slurry). Bring to a gentle simmer.
Thicken: Stir the cornstarch slurry, then drizzle it in while stirring. Simmer 1–2 minutes until the sauce turns glossy and coats the chicken and vegetables.
Finish: Taste and adjust.
Add a splash of water if too thick, or a touch more honey or vinegar to balance. Garnish with green onions and sesame seeds.
Serve: Spoon over cauliflower rice, brown rice, quinoa, or zucchini noodles. Keep portions moderate to maintain the low-calorie focus.