Butterfly chicken (cut lengthwise to make it thinner, but don't bother separating the two pieces), then season on both sides with sea salt and pepper.
Heat olive oil in a cast iron skillet over medium heat until shimmering, then add chicken and brown for 10 minutes a side or until completely cooked through.
Let chicken cool, then chop.
While cooking and cooling chicken, chop your salad veggies and halve the mozzarella. (Keep the size of your chopped ingredients roughly the same, other than the green onion.)
Add lettuce to a large plate or bowl, top with chicken and veggies, and drizzle with your own favorite salad dressing to taste.
Chicken, Avocado, and Mozzarella Chopped Salad itself is naturally gluten free -- I served mine with skinny garlic toast, and you can keep the meal gluten free by using gluten free bread or choosing a different side.
Chicken, Avocado, and Mozzarella Chopped Salad from Mashup Mom: https://www.mashupmom.com/chicken-avocado-mozzarella-chopped-salad/