Place sausages and water in a large skillet; bring to a boil. Reduce heat; cover and simmer for 10 minutes. Uncover; cook 5-10 minutes longer or until meat is no longer pink; drain. Remove sausages and keep warm.
In the same skillet, saute pepper and onion in oil until tender. Return sausages to pan. Stir in spaghetti sauce and basil; heat through. Serve sausages on buns with sauce and cheese.