Slow Cooker Spaghetti Sauce

1 lb. Italian Sausage
1/2 onion, diced
2-3 cloves garlic, minced
2 cans diced tomatoes
1 can tomato paste
1 can diced olives
1 can mushroom stems & pieces
1 tsp. freshly ground black pepper
1/4 tsp. freshly ground sea salt
1 Tbsp. dried basil
1 Tbsp. dried oregano
1 tsp. dried Italian Seasoning
2 Tbsp. dried parsley

Brown and drain Italian Sausage. Add to slow cooker with all other ingredients. Cook on Low 5-7 hours. Serve over pasta with parmesan or cheddar cheese.