Slow Cooker: Ravioli Casserole 1.5 lbs. lean ground beef 1 onion, chopped 1 clove garlic, minced 1 (15 oz.) can tomato sauce 1 can stewed tomatoes 1 tsp. oregano 1 tsp. Italian seasoning salt/pepper 10 oz. frozen spinach, thawed (I used fresh spinach) 16 oz. bowtie pasta, cooked 1/2 cup parmesan cheese, shredded 1 1/2 cup mozzarella, shredded *Brown ground beef with onion and garlic.  Put in crock-pot and add sauce, tomatoes and seasonings. Cook for 6-7 hours on low.  Add the last 4 ingredients during the last 30 minutes of cooking and turn crock-pot to high.  I added the fresh spinach, pasta, parmesan and 1 cup of the mozzarella and I mixed it all up really well.  Then I added the last 1/2 cup of mozzarella to melt on the top.