Start by finely chopping the chicken breast into small pieces. This will help it cook quickly and evenly. Next, chop the mushrooms, green onions, and chestnuts. Set these ingredients aside.
In a frying pan or wok, heat the canola oil over medium-high heat. Add the chopped chicken and cook until it is no longer pink, about 5-7 minutes. Stir frequently to ensure even cooking.
Once the chicken is cooked through, add the chopped mushrooms, green onions, and chestnuts to the pan. Stir to combine and cook for another 3-4 minutes, allowing the vegetables to soften slightly.
Pour in the soy sauce, hoisin sauce, and Sriracha. Stir well to combine all the ingredients and let it cook for an additional 2-3 minutes. This will help the flavors meld together beautifully.
Remove the pan from the heat. To serve, take a piece of lettuce and spoon a generous amount of the chicken mixture into the center. Top with fresh cilantro leaves for added flavor.
Wrap the lettuce around the filling, and enjoy your Chinese Chicken Lettuce Wraps fresh and warm!