Bring a large pot of salted water to a boil and cook the rigatoni according to package directions until al dente. Drain and set aside.

In a mixing bowl, combine the ground beef, breadcrumbs, egg, 1 teaspoon salt, and 1/2 teaspoon black pepper. Mix gently with your hands until just combined, then roll into 1-inch meatballs.

Heat the olive oil in a large skillet over medium heat. Add the meatballs and cook, turning occasionally, until browned on all sides, about 6 minutes. Remove the meatballs to a plate.

In the same skillet, add the diced onion and cook for 3 minutes until softened. Stir in the minced garlic and cook for 1 minute more.

Pour in the crushed tomatoes and bring the sauce to a simmer. Return the meatballs to the skillet, cover, and cook for 10 minutes until the meatballs are cooked through.

Lower the heat and stir in the heavy cream and chopped basil. Simmer for 2 minutes, then taste and adjust salt and pepper as needed.

Add the drained pasta to the skillet and toss to coat evenly with the sauce. Sprinkle with Parmesan cheese before serving.