Combine ground sirloin, bread crumbs, 1/4 cup pasta sauce, and salt; mix well.

Shape mixture into 12 meatballs.

Coat a large nonstick skillet with cooking spray; place over medium-high heat.

Add meatballs to the skillet and sauté for 5 minutes, or until browned.

Add green bell pepper and onion to the skillet.

Cook for 3 minutes, stirring occasionally.

Add the remaining pasta sauce to the skillet.

Cover and reduce heat to medium-low.

Simmer for 8 minutes, or until meatballs are cooked through.

Spoon the meatball mixture into the split hoagie or French rolls.

Top with shredded mozzarella cheese and fresh basil (optional).

Let stand for 1 minute before serving to melt cheese slightly.