Preheat the oven to 375°F.

In a large pot of boiling salted water, cook the penne pasta according to package directions to one minute shy of al dente. The pasta will continue to cook and soften in the sauce as the casserole bakes in the oven. Drain the pasta and set aside. While the pasta is cooking, cook the bacon and prepare the remaining ingredients.

In a large (12-inch) skillet over medium-low heat, cook the bacon pieces for 22-25 minutes or until all the fat has rendered and the bacon is crispy. Using a slotted spoon, transfer the bacon to a paper towel-lined plate (reserving ¼ cup of the crispy bacon for the top of the casserole) to drain off all the excess grease. Remove all but 1 tablespoon of the bacon grease from the skillet.

In a large bowl, toss the chicken pieces with 2 tablespoons dry ranch seasoning mix, salt, and black pepper until evenly coated with the seasonings.

Increase the heat to medium-high, add 1 tablespoon butter to the skillet with the 1 tablespoon of bacon grease. Once the butter has melted, add the seasoned chicken pieces in a single layer and cook for 8-10 minutes or until no pink remains. Transfer the cooked chicken to a clean plate. Drain off any excess moisture from the skillet before continuing.

Reduce the heat to medium, add the remaining 4 tablespoons of butter and allow it to melt. Add the onions, garlic, Italian seasoning, and dried basil. Cook for 2-3 minutes or just until the onions are soft and translucent.

Sprinkle the all-purpose flour over the softened onions and stir to combine until all the flour has been absorbed into the butter and no dry pockets remain.

Slowly whisk in the chicken broth and heavy cream until no lumps of flour remain.

Add the cream of chicken soup and remaining 1 tablespoon dry ranch seasoning whisking until smooth.

Cook for 4-6 minutes, or until the sauce starts to bubble and thicken enough to coat the back of a spoon.

Turn off the heat to the skillet and stir in the shredded parmesan cheese until fully melted.

Add the drained pasta, cooked chicken, and all but ¼ cup of the crispy bacon to the sauce. Gently stir to combine all the ingredients until well combined and all the pasta is coated in the sauce.

Transfer to a 9x13 baking dish, top with the shredded mozzarella cheese and ¼ cup crispy bacon.

Bake uncovered for 25 minutes or just until the cheese is melted and the sauce is bubbly around the edges.

Allow the chicken bacon ranch casserole to rest for 2-3 minutes before garnishing with fresh chopped parsley and serving.