Wash the lettuce. Let dry on the paper towels. Cut the bottom of the lettuce, if needed.
Cut the chicken into small pieces (about 2×2 cm). In a bowl, stir gently to coat the chicken, soy sauce and corn starch. Let stand at room temperature about 15 min.
In a small bowl, combine all sauce ingredients.
In a wok or large skillet, heat the oil over medium-high heat. Add the chicken.
Stir-fry about 2-3 min., until lightly golden.
Pour the sauce and mix to coat the chicken.
Add the veggies, peanuts. Cook for 2 min.
Spoon the veggies and chicken into the lettuce leaves. Top with red cabbage, chili pepper, spring onions (optional).