Pour jar #1 of the pasta sauce and 1/2 cup of the beef broth in the bottom of the slow cooker.
Break the pasta in half. Sprinkle half of it on top the sauce (scatter it around so it's touching as little as possible).
Pour in the meatballs and top with the other half of the pasta.
Spoon out chunks of the cream cheese and place them all around the crockpot
Top with another pasta sauce and sprinkle on the mozzarella cheese.
Cover and cook on high for 3 1/2 to 5 hours (I've never tried it on low).
You can either stop here and eat or you can continue with the directions.
Stopping here will give you more of a spaghetti casserole with a lot less sauce.
If you want a more traditional, creamy cheesy pasta...continue with the directions below
Uncover and stir well. Add as much of the pasta sauce and remaining beef broth to get the sauce to the consistency you prefer. I added another full jar of sauce and another 1/2 cup beef stock.
Cover and cook on low until heated (20 minutes or so); or even up to 2 hours if you have other stuff to do.
If you're gonna be busy more than 2 hours, just turn it to warm and it's fine for several hours.