Step 1: Cook pasta according to package directions in a large pot of salted water until al dente. Drain well and set aside.
Step 2: While the pasta cooks, heat a large skillet over medium-high heat. Add chopped bacon and cook until crispy. Remove bacon with a slotted spoon, place on a paper towel-lined plate, and chop when cool. Reserve about 1-2 tablespoons of bacon drippings in the skillet, discarding any excess.
Step 3: Season the cubed chicken with garlic powder, onion powder, salt, and pepper. Add chicken to the same skillet (add a touch of olive oil if there isn't enough bacon fat). Cook until chicken is cooked through and lightly golden brown, about 5-7 minutes. Remove chicken from skillet and set aside with the bacon.
Step 4: Reduce heat to medium. Add butter to the skillet and let it melt. Whisk in the all-purpose flour and cook for 1-2 minutes, stirring constantly, to create a roux.
Step 5: Gradually whisk in the chicken broth and milk/half-and-half until the mixture is smooth. Bring to a gentle simmer, stirring frequently, until the sauce begins to thicken, about 3-5 minutes.
Step 6: Stir in the softened cream cheese, dry ranch seasoning mix, and Italian seasoning until the cream cheese is fully melted and the sauce is smooth. Remove from heat and stir in the shredded cheddar cheese until completely melted and incorporated.
Step 7: Add the cooked and drained pasta, cooked chicken, and chopped crispy bacon back into the skillet with the sauce. Toss everything gently until the pasta, chicken, and bacon are evenly coated in the creamy ranch sauce.
Step 8: Serve immediately, garnished with fresh chopped parsley if desired. Enjoy your ultimate creamy chicken bacon ranch pasta!