Follow these easy steps to create your Loaded Chicken and Potato Casserole:

1. Preheat Oven: Preheat your oven to 350°F (175°C).
2. Prepare Potatoes: In a large pot, boil diced potatoes in salted water until tender, about 10-15 minutes. Drain and set aside.
3. Mix Chicken and Veggies: In a large bowl, combine cooked chicken and frozen mixed vegetables (if using).
4. Create Sauce: In a separate bowl, whisk together sour cream, milk, ranch dressing, garlic powder, onion powder, paprika, salt, and black pepper.
5. Combine Ingredients: Add the drained potatoes to the chicken mixture. Pour the sauce over the chicken and potatoes, mixing well until everything is evenly coated.
6. Prepare Casserole Dish: Grease a 9×13-inch casserole dish with cooking spray and spread the mixture evenly in the pan.
7. Add Cheese: Sprinkle shredded cheddar cheese evenly over the top of the casserole.
8. Bake: Place the casserole in the preheated oven. Bake for 30-35 minutes until bubbly and the cheese is melted and golden.
9. Cool: Once cooked, remove from the oven and allow the casserole to rest for 5-10 minutes before serving.
10. Garnish: Sprinkle crumbled bacon and chopped green onions on top just before serving for extra flavor and presentation.

This simple approach ensures that you achieve the wonderful, loaded flavors expected from this casserole.