Fill a large pot with generously salted water, bringing it to a rolling boil. Add pasta and cook until al dente, about 2-3 minutes less than package instructions. Drain and set aside, reserving a cup of pasta water.

In a large skillet, heat olive oil over medium-high heat. Add ground beef, breaking apart with a spatula. Cook for about 4-5 minutes until browned and cooked through. Drain excess fat if necessary, season with salt and pepper.

Lower the heat to medium and add diced onion and bell pepper to the skillet. Sauté for about 3 minutes until onion is translucent. Stir in minced garlic and mushrooms, cooking for an additional 2 minutes until softened.

Stir in tomato paste and let cook for a minute until it darkens slightly. Add Italian seasoning, smoked paprika, red pepper flakes, beef broth, and diced tomatoes. Reduce heat to low and simmer for about 4-5 minutes.

In a small bowl, mix together Greek yogurt and cottage cheese until smooth. Gently stir this creamy blend into the beef mixture with Parmesan cheese and cook for another 3 minutes.

Add drained pasta to the skillet, tossing gently with the creamy sauce. If too thick, incorporate reserved pasta water until desired consistency is achieved.

Sprinkle with shredded mozzarella cheese, cover, and let melt for about 2 minutes on low heat. Garnish with fresh herbs if desired and serve immediately.