Bring a large pot of salted water to a rolling boil. Add the whole wheat penne pasta and cook until it’s al dente, about 1-2 minutes less than the package directions indicate. Drain the pasta, reserving ½ cup of the pasta water, and set aside.

In a large skillet, heat a bit of oil over medium-high heat. Add the diced onion and minced garlic, sautéing until the onions are translucent, about 3-4 minutes. Add the lean ground beef, cooking until it reaches an internal temperature of 165°F, around 8-10 minutes. Drain any excess grease and season with Italian seasoning, salt, and black pepper.

In a mixing bowl, combine the full-fat cottage cheese and plain Greek yogurt. Stir until the mixture is smooth and creamy.

Preheat your oven to 375°F. In a large baking dish, layer the cooked penne pasta evenly across the bottom. Spoon the browned beef mixture on top, followed by the marinara sauce. Gently fold the layers together.

Dollop the creamy cottage cheese and Greek yogurt mixture over the pasta and beef layers. Use a spatula to spread it evenly, then sprinkle shredded mozzarella and grated Parmesan cheese generously on top.

Place the assembled baking dish into the preheated oven. Bake for 20-25 minutes, until the cheese is golden brown and bubbling. Let the dish rest for 5-10 minutes before serving, and garnish with fresh parsley.