In large frying pan, over medium heat, heat 1/2 of the cooking oil, then sauté spinach, cilantro, onion, garlic, ginger, & chile. About 3 minutes. Set aside.
In same pan, brown ground chicken using the other 1/2 of the cooking oil, drain grease. Add previously sautéed veggies back in, along with the fish sauce, lime zest, and salt. Toss, stir to warm & combine.
Fill lettuce leaves with chicken mixture, top with remaining/optional ingredients.