Preheat oven to 350F. Grease a cookie sheet or line it with parchment paper and set aside. In a large bowl, mash kidney beans. Combine the beans with all remaining ingredients except breadcrumbs until evenly combined.
Using your hands, mold mixture into walnut-sized balls and roll gently in breadcrumbs. Place on cookie sheet. Bake for 25 to 30 minutes, or until lightly brown and a firm outer crust forms.
Set aside for 10 to 15 minutes before serving, allowing the balls to cool and firm up. Serve with your favorite marinara poured over top.