01 - Set oven temperature to 375°F and allow to fully preheat.
02 - Boil egg noodles in a large saucepan as directed on packaging, then drain thoroughly and set aside.
03 - Heat a large skillet over medium heat and cook the ground beef until evenly browned, breaking it apart with a spoon as it cooks. Drain off the excess fat.
04 - Add diced onion, minced garlic, and diced bell pepper to the cooked beef. Sauté until vegetables are softened, about 3 to 4 minutes.
05 - Incorporate tomato sauce, diced tomatoes with their juices, beef broth, oregano, basil, salt, and black pepper. Stir well and simmer for 5 minutes to allow flavors to blend.
06 - Remove skillet from heat. Add cooked noodles and sour cream, folding mixture until evenly combined.
07 - Transfer the beef and noodle mixture into a 9x13-inch baking dish. Spread evenly and top with shredded cheddar cheese.
08 - Bake uncovered for 20 to 25 minutes, or until the casserole is bubbling and the cheese is fully melted.
09 - Sprinkle chopped parsley over the top before serving, if desired.