01 - Bring a large pot of salted water to a rolling boil. Add pasta and cook according to package directions until al dente. Drain thoroughly and set aside.
02 - Heat a large skillet over medium heat. Add chopped bacon and cook until crispy, about 5-7 minutes. Remove with a slotted spoon and drain on paper towels, reserving approximately 1 tbsp of bacon drippings in the skillet.
03 - Add butter to the reserved bacon fat in the skillet. Once melted, add minced garlic and sauté for 30 seconds until fragrant, being careful not to burn.
04 - Reduce heat to medium-low. Add softened cream cheese and stir until melted and smooth. Pour in chicken broth, heavy cream, and ranch seasoning packet. Whisk continuously until fully incorporated and creamy, about 3-4 minutes.
05 - Gradually stir in shredded cheddar and grated parmesan cheese. Continue stirring until completely melted and sauce has thickened slightly, about 2 minutes.
06 - Add cooked chicken breast and half of the crispy bacon to the sauce. Stir gently to combine and heat through, about 2-3 minutes.
07 - Add the drained pasta to the skillet. Using tongs or a large spoon, toss thoroughly until every piece of pasta is evenly coated with the creamy sauce.
08 - Divide the pasta among four serving plates. Top evenly with remaining crispy bacon and sliced green onions. Finish with freshly ground black pepper to taste. Serve immediately while warm.