Cook Bacon and Steam Broccoli - Fry or bake the bacon in the oven until crispy. Meanwhile, blanch the broccoli in boiling water for about 2-3 minutes. Then, crumble the bacon into small pieces.
Prepare the chicken - Cut the chicken breasts into bite-sized pieces and pan-sear them for 5-6 minutes over medium-high heat. Alternatively, you can use leftover shredded rotisserie chicken breast.
Preheat the oven to 375°F (190°C) and grease a 9x13-inch glass casserole baking dish.
Assemble - In a large bowl, combine the cooked chicken, bacon bits, broccoli, ranch dressing, 1 cup of cheddar cheese, and mozzarella. Toss everything together until well incorporated. If you want extra ranch flavor, mix in about 3 tablespoons of ranch seasoning.
Transfer the chicken mixture to the prepared casserole dish, and top it with the remaining cheddar cheese and bacon.
Bake for 20-25 minutes in the preheated oven, or until the cheese is melted and the chicken casserole appears golden brown on top.
Garnish with fresh parsley and bacon bits. Enjoy!
If you're using leftover chicken, you'll need about 3 cups of leftover shredded chicken.