Heat the Oil: In a large skillet, pour in 2 tablespoons of olive oil and heat over medium heat. Once shimmering, add one chopped onion. Sauté for about 5 minutes until translucent, then stir in 3 minced garlic cloves and cook for an additional minute.

Cook the Beef: Add 1 pound of ground beef, breaking it apart as it cooks. Cook for about 8 minutes until nicely browned.

Prepare the Ragu: Stir in 2 tablespoons of tomato paste, followed by 28 ounces of crushed tomatoes and 1 cup of broth. Add 1 teaspoon each of oregano and thyme, with salt and pepper to taste. Simmer for 20-25 minutes.

Cook the Rigatoni: In a large pot of boiling salted water, add 12 ounces of rigatoni and cook until al dente, about 10-12 minutes. Drain and set aside to cool.

Stuff the Rigatoni: Once the ragu thickens, remove from heat. Use a piping bag to stuff each rigatoni with the ragu and place in a greased baking dish.

Add the Cheese: Preheat oven to 375°F (190°C). Sprinkle mozzarella cheese over the stuffed rigatoni, and finish with Parmesan cheese.

Bake to Perfection: Place in the oven and bake for 20-25 minutes until the cheese is bubbly and golden brown.

Garnish and Serve: Let it sit for 5 minutes, then garnish with parsley. Serve hot.