Prep: To start, gather all the ingredients, preheat the oven to 375 degrees F, and lightly grease a 9x13 casserole dish. Boil the pasta: First, place a large pot of water over medium-high heat and cook the pasta per package directions, aim for al-dente. After that, drain it and set it aside. Cook the bacon: Meanwhile, place a large non-stick skillet over medium-high heat and cook the bacon until crispy. After that, set it aside to drain on paper towels. Also, make sure to leave about 2 tablespoons of grease in the skillet. Alternatively, use pre-cooked bacon. Brown the chicken: Next, add the cubed chicken and cook it. Alternatively, use rotisserie chicken and skip this step altogether. Transfer it to a large mixing bowl. Cook the veggies: Then, add the onion, garlic, and bell pepper to the same skillet and cook until tender. Also, add them to the bowl with the meat. Make the Sauce: Finally, let's make the incredibly cheesy sauce. For that, melt some butter into the same skillet and add the flour, make sure to stir until paste forms. After that, slowly, while still stirring pour in the milk. Next, stir in the Ranch seasoning, condensed cream of chicken soup, and cream cheese. Add cheese: At this time, is important to reduce the heat to low, and stir in the shredded cheese until melted. Lastly, turn off the heat, the sauce is ready! Combine: Next, add the cooked pasta to the bowl with the meat and veggies and add the sauce. Afterward, toss gently until well combined and transfer the mixture to the prepared baking dish. Toppings: Then, add the remaining cheese, sprinkle the panko bread crumbs on top, and also add the crispy bacon. Bake: Next, bake the casserole for 20-30 minutes until the cheese is hot and bubbly! Serve: At last, let the dish cool for 10 minutes before serving. Sprinkle some chopped green onions on top and serve.