Fill a large pot with water, add a generous pinch of salt, and bring to a boil. Add jumbo shells and cook according to package directions until just al dente. Drain and keep warm.

Heat a large skillet over medium. Add the ground beef and break it up with a spoon. Cook until there’s no pink remaining, stirring occasionally to brown evenly.

Carefully drain excess fat, leaving a thin film in the pan to carry flavor. Return the skillet to medium heat.

Pour the diced tomatoes with their juices into the beef. Stir in garlic powder, onion powder, and a pinch of salt and pepper. Let the mixture simmer for 3 to 5 minutes.

Reduce heat to low and stir in the cream or milk. Add the shredded cheddar a handful at a time, stirring after each addition until the sauce becomes smooth and creamy.

Taste and adjust seasoning as needed.

Add the cooked shells to the skillet. Gently toss to coat each shell in the creamy tomato and beef sauce. Heat through for another minute or two.

Serve straight from the skillet or transfer to plates. Sprinkle with chopped fresh parsley if using and serve hot.