Make meatballs: In a large bowl, mix together ground beef, bread crumbs, Parmesan, parsley, egg, salt, and crushed red pepper flakes. Form into 16 meatballs and place in the bottom of a Crock Pot.
In another large bowl, mix together crushed tomatoes, tomato paste, onion, oregano, and garlic. Season with salt, pepper and a pinch of red pepper flakes. Pour sauce over meatballs. Cover Crock Pot with lid and cook on high for 3 hours or on low for 5 hours.
Add broth spaghetti to Crock Pot, breaking noodles in half to fit and stirring to coat noodles. Replace lid and continue cooking on low for 1 ½ hour more hours, stirring about every 30 minutes and breaking up any clumps of noodles and adding more broth as needed.
Garnish with Parmesan and parsley before serving.
