Preheat your oven to 350°F (175°C) and grease a 9x13-inch baking dish.

In a large pot, bring salted water to a boil. Add the egg noodles and cook until slightly firm, about 5–7 minutes. Drain and set aside.

In a large mixing bowl, combine the cream of chicken soup, sour cream, and milk. Add garlic powder, onion powder, salt, and pepper, and whisk until smooth.

Gently fold in the cooked egg noodles and shredded chicken into the sauce mixture. Stir in half of the cheddar cheese.

Pour the mixture into the greased baking dish, top with the remaining cheddar cheese, and add bacon if using.

Cover with foil and bake for 20 minutes. Remove foil and bake for another 10–15 minutes until cheese is bubbly and golden brown.

Let the casserole rest for about 5 minutes before serving. Garnish with chopped green onions if desired.