Bring a large pot of water to a boil and salt it well.
Cook the pasta until just tender.
Before draining, reserve 1 cup of pasta water.
Drain the pasta and set it aside.
Cook the bacon until crisp.
Remove the bacon from the pan and chop it.
Heat the butter and olive oil in a large skillet over medium heat.
Add the diced chicken to the skillet.
Season the chicken with 1/2 tsp kosher salt, black pepper, garlic powder, and onion powder.
Cook the chicken until it is cooked through.
Sprinkle the flour over the chicken.
Stir for 60 seconds.
Whisk the milk in slowly until the sauce turns smooth and thick.
Stir in the cubed cream cheese until fully melted.
Add the shredded cheddar and shredded mozzarella.
Stir on low heat until the cheese melts and the sauce looks glossy.
Mix in the ranch dressing.
Taste the sauce and add the remaining kosher salt if needed.
Add the cooked pasta to the skillet.
Add the chopped bacon to the skillet.
Toss until everything is evenly coated.
Add reserved pasta water a splash at a time until the sauce turns silky.