Preheat your oven to 350°F.
Bring a large pot of salted water to a boil. Add the rotini pasta and cook until al dente. Drain and set aside.
In a large skillet, sauté the minced garlic in reserved bacon grease for 1-2 minutes until lightly toasted.
Add the cream cheese to the skillet. Heat over low until the cream cheese melts and becomes smooth.
Whisk in the ranch seasoning mix and whole milk, then cook until combined and slightly thickened, about 2-3 minutes.
Stir in 1 cup of shredded mozzarella cheese until melted.
In a large bowl, combine the cooked pasta, half the bacon, and chopped chicken. Pour the cream cheese mixture over and stir well.
Transfer the mixture into a 9x13 casserole dish, spreading evenly.
Top with the remaining mozzarella and crumbled bacon.
Bake in the preheated oven for 20-25 minutes until the cheese is bubbly and slightly browned.
Garnish with fresh parsley and serve hot.