Mash sweet potato until smooth. Add eggs and bread crumbs and stir. Season with salt and pepper. Gently stir in black beans. Pour oil into pan and heat over med./high heat. Make sweet potato mixture into patties and gently place in the hot pan. Cook until browned on each side. Serve open faced on slice of bread of half a bun or better yet use grilled red peppers in place of bread. Top patty with slaw and serve.