Heat sesame oil in a large skillet over medium heat. Saute the onions, ginger and garlic until sizzling. Add the ground turkey and cook through. Use a potato masher to grind the turkey into smaller pieces as it's cooking.
Stir in the lime juice, fish sauce, brown sugar and chili garlic sauce and cook until liquid is absorbed.
Remove from heat and stir in the cilantro, mint and scallions. Spoon the turkey mixture into lettuce leaves and top with chopped peanuts, carrots and additional fresh herbs.