Italian Sausage and Peppers

1 1/2 lbs. good Italian Sweet Sausages
2 tbsp. Olive oil
3 large sweet bell or roasting peppers, sliced (mixed colors are nice)
1 medium Onion, sliced
2 cloves fresh garlic, minced
1/4 cup Fresh parsley (chopped)
Salt & cracked black pepper to taste
1 lb. penne or spaghetti, cooked 

2 large tomatoes, diced (optional)

Boil spaghetti or penne to taste.  In a large heavy skillet brown sausages well on all sides.  Add 1/2 cup-1 cup of water, cover and simmer on low heat for 10 min. After sausage has simmered, drain any extra water away and add onions and peppers to the skillet and cook until onion is beginning to become translucent.  Add garlic, parsley, salt and pepper and tomatoes (if using) and cook for about 3 minutes more.  Serve over pasta and pass parmesan cheese.