Preheat your oven to 350°F (175°C).

In a large pot, boil salted water and add the egg noodles. Cook until al dente, about 6-8 minutes. Drain and rinse.

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

Fold in the cooked chicken and half the shredded cheddar cheese until combined.

Gently combine the cooked egg noodles with the creamy chicken mixture until evenly coated.

Spread the noodle and sauce mixture into a greased 9x13-inch baking dish and top with remaining cheddar cheese.

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

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