Whisk the sauce. In a small bowl, combine soy sauce, rice vinegar, sesame oil, hoisin (or honey), sriracha, chicken broth, and cornstarch. Stir until smooth and set aside.
Prep the veggies. Dice the onion and bell pepper, mince the garlic, grate the ginger, and slice the mushrooms. Wash and separate the lettuce leaves.
Pat them dry so they stay crisp.
Brown the chicken. Heat the neutral oil in a large skillet over medium-high. Add the ground chicken and break it up with a spatula. Cook until no longer pink and lightly browned, about 5–7 minutes.
Season with a pinch of salt and pepper.
Sauté aromatics and veggies. Add the onion, garlic, and ginger to the skillet. Cook 1–2 minutes until fragrant. Stir in bell pepper, carrots, and mushrooms.
Cook another 3–4 minutes until tender-crisp.
Add the sauce. Give the sauce a quick stir, then pour it into the pan. Toss to coat. Simmer for 1–2 minutes until slightly thickened and glossy.
Taste and adjust seasoning with a splash more soy or vinegar if needed.
Finish with freshness. Turn off the heat. Stir in half the scallions and a sprinkle of sesame seeds. This keeps the flavors bright.
Assemble the bowls. For meal prep, portion the chicken mixture into containers.
Keep lettuce leaves, extra scallions, herbs, and lime wedges separate. When ready to eat, spoon the chicken into lettuce cups and top with more scallions, sesame seeds, and herbs.