In a bowl, add the ground turkey and other marinade ingredients (soy sauce, vinegar, and sesame oil.) Set aside.
In a separate bowl, make the sauce by combining all of the sauce ingredients and whisking until smooth. Set aside.
Add a little olive oil to a large skillet or wok over medium-high heat. When the oil is hot at the turkey and stir and toss gently until cooked, about 2 minutes.
Add bell pepper, green onion, ginger, garlic and water chestnuts and brown rice. Cook for 1 minute.
Add the reserved sauce to the pan and cook for another minute or two until the sauce begins to thicken slightly. Serve warm, inside lettuce cups.