Season chicken with your favorite bbq rub and place on hot grill to cook on medium high heat until internal temperature reaches 165 degrees.
Cook the bacon in a skillet, or griddle until crispy.
Toast the buns on either the grill, or griddle.
Using a cutting board, add layer of shredded lettuce, then add chicken, bacon and tomatoes. Chop everything up, making sure its well mixed together.
Season with salt and pepper, add mozzarella cheese and ranch dressing.
Chop and mix one more time to incorporate all ingredients.
Load each sub with the chopped ingredients and serve.