01 - Set oven to 350°F (175°C) and allow to fully preheat.
02 - In a large skillet over medium heat, cook ground beef until it is thoroughly browned. Drain excess fat from the pan.
03 - Add finely chopped onion and minced garlic to the skillet. Sauté for 2 to 3 minutes until softened and fragrant.
04 - Incorporate diced tomatoes, tomato sauce, tomato paste, Italian seasoning, salt, and black pepper into the skillet. Stir well and let the mixture simmer for 10 minutes.
05 - Meanwhile, bring a large saucepan of salted water to a boil. Cook egg noodles according to package directions until just al dente, then drain thoroughly.
06 - In a mixing bowl, combine sour cream and cottage cheese until smooth.
07 - Lightly grease a 9x13 inch casserole dish. Layer half of the cooked noodles, top with half the sour cream and cottage cheese mixture, then add half of the beef-tomato mixture. Repeat layers with remaining noodles, cheese mixture, and beef.
08 - Scatter shredded cheddar cheese evenly over the surface of the final layer.
09 - Transfer casserole to oven and bake uncovered for 25 to 30 minutes, until the top is golden and bubbling.
10 - Allow casserole to rest for 10 minutes after baking before slicing and serving.