Cook the noodles: Begin by boiling a large pot of salted water and cooking the egg noodles according to the package instructions. Drain and set aside.
Brown the beef: In a large skillet over medium heat, add the ground beef, chopped onion, and minced garlic. Cook until the beef is browned and the onions are translucent, about 6-8 minutes. Drain excess grease.
Mix in the rest: Stir in the cream of mushroom soup, drained diced tomatoes, Italian seasoning, salt, and pepper. Add the cooked noodles and mix until well combined.
Create layers: In a greased 9x13 baking dish, spread half of the noodle-beef mix, sprinkle with 1 cup of cheese, and then add the remaining noodle-beef mix on top.
Finish with cheese: Pour the milk evenly over the casserole and top with the remaining 1 cup of shredded cheese.
Bake it up: Preheat the oven to 350°F (175°C) and bake for 25-30 minutes, until the cheese is bubbly and golden.
Enjoy: Let it cool for a few minutes before serving. Dish it up and enjoy the cheesy goodness!