Combine the water and salt in a large pot. Bring the water to a boil and add the jumbo shells. Boil for 8 min. or until tender. Drain the shells with a colander and run them under cold water for 2 min. Set aside.

Peel the onion with a paring knife and chop it with a kitchen knife. Peel and mince the garlic. Combine the beef, onion, and garlic in a frying pan.

Saute over medium until the ground beef is browned and the onions are tender. Stir regularly with a wooden spoon.

Drain the grease from the beef and transfer the mixture to a mixing bowl.

Preheat oven to 375F. Grate the Parmesan and cut the mozzarella into very small cubes, or you can also shred it, whichever you prefer. Wash and pat dry the parsley with a paper towel. Chop with a kitchen knife.

Add the breadcrumbs, eggs, Parmesan, mozzarella, salt, pepper, and parsley to the beef mixture. Stir with a wooden spoon to combine.

One at a time, using a spoon, stuff the jumbo shells well with the meatball mixture. As each jumbo shell is stuffed, place it in a 9" square baking pan. Then repeat for another 9" pan or use one very large pan. Top the shells with the pasta sauce. You want them to be nice and saucy and well-covered.

Bake the stuffed shells for 30 min. or until bubbly. Remove the pasta from the oven and let cool slightly.

Wash the parsley and pat dry with a paper towel. Chop with a kitchen knife. Divide the cooked stuffed shells between plates. Top each serving with chopped parsley and serve immediately.