Prep the lettuce: Gently separate the leaves of your butter or romaine lettuce. Rinse, pat dry, and chill in the fridge to keep them crisp.
Chop the aromatics: Mince the garlic, grate the ginger, slice the green onions, and finely chop mushrooms and peppers if using.
Make the sauce: In a small bowl, whisk soy sauce or coconut aminos, vinegar, sesame oil, sriracha, and sweetener if using.
Taste and adjust salt, heat, and sweetness.
Cook the chicken: Heat oil in a large skillet over medium-high. Add ground chicken, season lightly with salt and pepper, and break it up with a spatula. Cook until no longer pink and slightly browned in spots, about 5–7 minutes.
Add aromatics and veg: Stir in garlic, ginger, green onions (reserve some for garnish), and mushrooms/peppers if using.
Cook 2–3 minutes until fragrant and tender.
Sauce it up: Pour in the sauce and toss to coat. Let it simmer 2–3 minutes until slightly reduced and glossy. Adjust seasoning.
If you like it saucier, add a splash more aminos.
Assemble: Spoon warm chicken filling into chilled lettuce leaves. Top with sesame seeds, remaining green onions, cilantro, and a squeeze of lime.
Serve right away: The contrast of hot filling and crisp lettuce is key. Set out extra sauce and lime at the table.