Preheat oven to 400 degrees F. For croutons, cut corn bread into 1-inch cubes (about 4-1/2 cups). Place cubes in a 15x10x1-inch baking pan; lightly coat with cooking spray. Bake about 10 minutes or until crisp and golden. Remove from oven; sprinkle with the 2 tablespoons Parmesan cheese.
In a 12-inch skillet heat 1 tablespoon of the oil over medium heat. Add onion; cook for 4 to 5 minutes until tender. Stir in 2 tablespoons of the vinegar. Add beans; heat through. Transfer to a bowl; cover to keep warm.
Add remaining oil to skillet. Add greens; cook and stir, in batches if necessary, just until wilted. Sprinkle with salt and black pepper; drizzle with the remaining vinegar. To serve, top greens with beans and croutons. If desired, top with additional Parmesan cheese and sprinkle with crushed red pepper.