Italian Sausage Crockpot Soup

1 large brown onion, chopped

1/2 teaspoon minced garlic (I use bottled)

2 medium carrots , chopped

1 stalk celery , chopped

1 (14 1/2 ounce) can tomatoes , chopped & undrained

1 (8 ounce) can tomato sauce

1/2 teaspoon dried basil

1/2 teaspoon crushed dried rosemary

1 bay leaf

1 teaspoon crushed dried oregano

1/4 teaspoon crushed dried thyme

3 (14 ounce) cans chicken broth

1/2 cup orzo pasta

parmesan cheese , shredded