Make the sauce. In a small bowl, whisk soy sauce, rice vinegar, sesame oil, honey, sriracha (if using), and water. Taste and adjust sweetness or heat. Set aside.
Prep the veggies. Core and thinly slice the cabbage.
Slice the onion and carrots. Mince the garlic and ginger. Have everything ready—the cooking goes fast.
Brown the turkey. Heat a large skillet or wok over medium-high.
Add 1 tablespoon oil, then the ground turkey. Season with a pinch of salt and pepper. Cook, breaking it up with a spatula, until browned and cooked through, about 5–7 minutes.
Add aromatics. Push the turkey to one side.
Add a little more oil if the pan looks dry. Add the onion, garlic, and ginger. Cook 1–2 minutes until fragrant, then mix with the turkey.
Stir fry the cabbage and carrots. Add cabbage and carrots.
Toss well and cook 4–6 minutes, stirring often, until the cabbage softens but still has some bite. If the pan is crowded, cook in batches or cover for 1 minute to steam, then uncover to finish.
Add the sauce. Pour the sauce over the mixture. Toss to coat.
Cook 1–2 minutes until the sauce slightly reduces and clings to the turkey and cabbage. Stir in green onions.
Taste and finish. Adjust seasonings—more soy for salt, vinegar for brightness, or honey for balance. Sprinkle sesame seeds and extra green onion on top.
Serve hot over rice or on its own.