Bring a large pot of salted water to a boil. Cook the tubular macaroni pasta for 1 to 2 minutes less than package directions until slightly under al dente. Drain and set aside.

Heat olive oil in a large skillet over medium-high heat. Add the diced onion and sauté for 3 minutes. Add the ground beef, browning it thoroughly until a dark crust forms. Drain any excess grease.

Stir the minced garlic and tomato paste into the beef, cooking for 1 minute to remove the raw tomato flavor. Pour in the crushed tomatoes, beef broth, salt, and pepper. Simmer gently for 10 minutes until the sauce is thick and glossy.

Preheat oven to 375°F (190°C). Mix the cooked macaroni into the rich meat sauce until evenly coated. Transfer the mixture to a 9x13-inch white ceramic baking dish, spreading it into an even layer.

Cover the top of the casserole completely with the shredded cheddar and mozzarella cheeses. Bake uncovered for 15-20 minutes until the cheeses are melted and bubbly.

Turn the oven to broil for the final 2-3 minutes to achieve slightly browned, crispy caramelized cheese edges. Remove from the oven, let rest for 5 minutes, and garnish with fresh chopped parsley and coarse black pepper before serving.