Cook sausage and onion powder in skillet over medium heat for 6-8 minutes.

Stir in sauce, parsley, and salt.

Mix 1 cup mozzarella, and the ricotta and parmesan. ( Refrigerate remaining mozzarella.)

Spoon 1/4th sausage mixture into slow cooker, top with 5 noodles.

Spread half of the cheese mixture and 1/4th of the sausage mixture. Top with 5 noodles.

Add remaining cheese mixture and 1/4th sausage mixture.

Top with 5 remaining noodles and remaining sausage mixture.

Cook on low 4 to 6 hours, or until noodles are tender.

Sprinkle remaining mozzarella. Cover and let stand about 10 minutes, or until cheese is melted.