Follow these simple steps to create your Baked Cream Cheese Spaghetti Casserole:

1. Preheat the Oven: Preheat your oven to 350°F (175°C).
2. Cook the Spaghetti: In a large pot of salted boiling water, cook the spaghetti according to package instructions until al dente. Drain and set aside.
3. Mix Cream Cheese and Sour Cream: In a medium bowl, mix the softened cream cheese and sour cream until smooth and creamy.
4. Combine Sauces and Spices: Stir in the marinara sauce, garlic powder, Italian seasoning, salt, and pepper into the cream cheese mixture.
5. Combine with Spaghetti: In a large bowl, combine the cooked spaghetti with the cream cheese mixture until fully coated.
6. Layer Ingredients: In a greased 9×13 inch baking dish, spread half of the spaghetti mixture. Top it with half of the mozzarella and cheddar cheese.
7. Add Remaining Spaghetti: Layer the remaining spaghetti mixture on top, followed by the rest of the mozzarella and cheddar cheese.
8. Bake the Casserole: Cover the dish with aluminum foil and bake for 20 minutes. Then, remove the foil and bake for an additional 10-15 minutes until the cheese is bubbly and golden.
9. Let it Rest: Once out of the oven, let it cool for about 5-10 minutes. This helps the casserole set for easier serving.
10. Garnish and Serve: Sprinkle with fresh parsley if desired, then slice and serve warm.

By following these steps, you’ll have a delicious Baked Cream Cheese Spaghetti Casserole ready to impress your family and friends!