Fry sausage in cast iron skillet on medium heat until brown on all sides and cooked all the way through. Turn often to avoid burning.

Add water, bell peppers, and onion to skillet and cover. Reduce heat to medium low and cook another 15-20 minutes or until vegetables are soft. Continue to turn sausages as needed to avoid burning.

Place all cooked ingredients on hoagie roll, cover with cheese and serve.