Line bottom and sides of 6 quart slow cooker with foil. Lightly grease with nonstick spray.
In large bowl, combine ground beef, peppers, bread crumbs, Parmesan and eggs. Use clean hands to thoroughly mix together. Shape mixture into a loaf; place in slow cooker.
Cover; cook on Low heat setting 5 to 6 hours or until meat thermometer inserted in center of loaf reads 160°F.
Uncover; pour marinara sauce evenly over cooked meatloaf. Cover; cook on Low heat setting 15 minutes longer or until sauce is thoroughly heated.
Use sides of foil to remove meatloaf from slow cooker to cutting board. Let stand 10 minutes before slicing and serving.
Notes
Nutrition information is an estimate only.
If you cannot find Italian style bread crumbs, add 1 teaspoon Italian seasoning to mixture.