Cheesy Penne in the Crock Pot

1 lb. Italian sausage
15 oz can of tomato sauce
14 oz can of diced tomatoes
1 tsp dried oregano
1 clove garlic minced
1/4 cup olive oil
fresh mushrooms
2 tsp sugar
3/4 lb penne pasta
1 cup shredded mozzarella

Cook and drain sausage (I like to use smoked sausage). Put into Crock pot, add tomato sauce, diced tomatoes, oregano, garlic, olive oil, mushrooms, and sugar. Mix well. Cook on low for 6-7 hours. Boil penne pasta in pot of water 4-5 minutes less than package directions. Drain and put into Crock pot. Stir in pasta, and top with mozzarella cheese. Cook for 30 minutes more.