Step 1: Prepare the Ingredients

1. Preheat your oven to 350°F (175°C).
2. Cook the bacon in a skillet over medium heat until crispy. Drain on paper towels and crumble once cool. Set aside.
3. Dice the chicken breasts into bite-sized pieces and season with a little salt and pepper.

Step 2: Cook the Pasta

1. Bring a large pot of salted water to a boil. Add the pasta and cook until al dente, according to package directions.
2. Drain and set aside, reserving about ½ cup of the pasta cooking water.

Step 3: Sauté the Chicken

1. Heat a large skillet over medium heat and add the butter.
2. Once melted, add the diced chicken and cook for about 5-7 minutes, or until fully cooked and no longer pink.
3. Remove the chicken from the skillet and set aside.

Step 4: Make the Creamy Ranch Sauce

1. In the same skillet, add a bit more butter if necessary and sauté the diced onion and minced garlic for about 2-3 minutes until softened and fragrant.
2. Reduce the heat to low and stir in the cream cheese, allowing it to melt and blend with the onions and garlic.
3. Gradually whisk in the milk and stir until a smooth sauce forms.
4. Add the sour cream, ranch seasoning mix, and the reserved pasta cooking water. Mix well to combine.
5. Add the cooked chicken back to the skillet and let everything simmer for 2-3 minutes until the flavors meld together.

Step 5: Assemble the Bake

1. In a large mixing bowl, combine the cooked pasta, creamy ranch chicken sauce, and half of the shredded cheddar cheese. Stir until the pasta is well coated.
2. Transfer the pasta mixture to a greased 9×13-inch baking dish and spread it out evenly.
3. Sprinkle the remaining cheddar cheese and crumbled bacon on top.

Step 6: Bake

1. Place the baking dish in the preheated oven and bake for 20-25 minutes, or until the cheese is bubbly and golden on top.
2. Remove from the oven and let it cool for a few minutes before serving.