Slow Cooker Lasagna

In a skillet, cook beef, onion and garlic over medium heat until meat is no longer pink; drain.

Add the tomato sauce, water, tomato paste, salt and oregano; mix well. Spread 1/4 of the meat sauce in an ungreased 5-quart slow cooker. Arrange 1/3 of the noodles over the sauce. Combine the cheeses; spoon 1/3 of the mixture over the noodles. Repeat layers twice. Top with remaining meat sauce. Cover and cook on low for 4 to 5 hours or until noodles are tender.