Canned beans supply fill-you-up protein at a fraction of the cost, fat and calories of ground beef or turkey. In our sloppy joes, we dress navy beans in mustardy tomato sauce that has all the familiar flavor of the meaty original.
In a large skillet, heat olive oil over medium heat. Add mushrooms, onion and green pepper; cook 5 to 7 minutes or until tender, stirring occasionally.
Push vegetables to one side of skillet. Add half of the navy beans; mash with potato masher or fork. Stir in remaining beans, tomato sauce, brown sugar, Worcestershire sauce, mustard, chili powder and salt. Simmer, uncovered, over medium-low heat for 10 to 12 minutes, stirring occasionally, until thickened enough to mound. Stir in sunflower kernels. Spoon onto toasted buns lined with spinach leaves.