Brown the beef, sausage and onion in a skillet for 10 minutes, breaking the meat into small crumbles, until it reaches 160°F.
Drain the fat, stir in the garlic for 30 seconds, and transfer the mixture to a 6-quart crockpot.
Add the crushed tomatoes, tomato sauce, broth, oregano and salt and cook covered on low for 5 1/2 hours.
Stir in the broken noodles and cook on high for 25 to 35 minutes until tender but not swollen.
Place 1/4 cup ricotta in each bowl, ladle soup around it, and divide the mozzarella over the 8 servings.