Italian Sausage Tomato Tortellini Soup

Italian Sausage (casings removed)

medium onion (chopped)

garlic (minced)

diced tomatoes)

tomato sauce

vegetable or chicken broth

package (12-ounces tortellini (I used cheese))

fresh arugula (spinach or kale would work as well)

salt and fresh ground pepper (to taste)

shredded parmesan cheese for topping (optional)