Preheat the oven to 350°F (175°C).
Cook the egg noodles according to package instructions until al dente. Drain and set aside.
In a large skillet, heat olive oil over medium heat. Add diced onion and cook until softened, about 3-4 minutes.
Add minced garlic and cook for 1 minute until fragrant.
Add ground beef to the skillet. Cook, breaking it apart with a spoon, until browned and cooked through, about 6-8 minutes. Drain excess fat.
Stir in tomato sauce, diced tomatoes with their juice, Italian seasoning, salt, and black pepper. Simmer for 5 minutes to blend flavors.
In a large mixing bowl, combine the cooked egg noodles and the ground beef tomato mixture. Mix well.
Transfer the mixture to a greased 9×13 inch baking dish. Spread evenly.
Sprinkle shredded cheddar and mozzarella cheese evenly over the top.
Bake uncovered in the preheated oven for 25 minutes, or until the cheese is melted and bubbly.
Remove from oven and let cool for 5 minutes before serving.