Preheat & Prep: Preheat your oven to 350°F and grease a 9x13-inch baking dish generously with nonstick cooking spray.

Brown the Beef: In a large skillet over medium-high heat, brown the lean ground beef and chopped yellow onion until the beef is fully cooked through, about 10 minutes. Drain any excess grease from the pan. Add the minced garlic and cook for 1 minute more until fragrant.

Simmer the Sauce: Stir in the tomato sauce and Italian seasoning, bringing the skillet to a gentle simmer. Let it simmer for 5 minutes, stirring frequently. Season to taste with Kosher salt and freshly ground black pepper. Remove from the heat and set aside.

Boil the Noodles: While you are making the meat sauce, cook the egg noodles according to the package directions in a large pot of salted boiling water. Ensure you cook them slightly underdone (al dente). Drain well and set aside.

Mix the Dairy Base: In a large mixing bowl, stir together the sour cream and cottage cheese until blended. Add the warm, drained egg noodles and season with salt and pepper to taste. Stir gently to completely coat the noodles.

Layer the Casserole: Transfer exactly half of the creamy egg noodle mixture into the prepared 9x13 baking dish. Top it evenly with half of the meat sauce. Top with the remaining egg noodle mixture, followed smoothly by the remaining meat sauce.

Bake: Top the entire casserole evenly with the freshly grated cheddar cheese. Bake uncovered for 30 minutes, or until the sauce is bubbly and the cheese has completely melted.

Rest & Serve: Let the hot casserole cool and rest for 10 minutes before serving. Enjoy!