Cook the Spaghetti: Bring a large pot of salted water to a boil. Add the spaghetti and cook according to the package instructions until al dente. Drain and return the spaghetti to the pot. While the spaghetti is still hot, add the softened cream cheese and stir until the noodles are evenly coated. Set aside.

Prepare the Meat Sauce: In a large skillet over medium heat, brown the ground beef until fully cooked. Drain any excess fat. Add the diced green bell pepper, diced onion, grated carrot, and minced garlic to the skillet. Cook for about 5 minutes, or until the vegetables are tender. Stir in the Italian seasoning and spaghetti sauce, mixing well.

Assemble the Casserole: Preheat your oven to 350°F. Lightly grease a 9×13-inch baking dish. Spread a small amount of the meat sauce on the bottom of the dish. Layer the cream cheese-coated spaghetti over the sauce. Pour the remaining meat sauce over the spaghetti, ensuring it is evenly distributed. Sprinkle the grated Parmesan cheese over the top, followed by the shredded mozzarella cheese.

Bake: Place the assembled casserole in the preheated oven and bake for 30 minutes, or until the cheese is melted and bubbly.

Serve: Remove from the oven and let the casserole sit for a few minutes before serving. Enjoy this comforting and creamy baked spaghetti with your family and friends!