Preheat a large frying pan on medium high heat. Lay your Duck breasts in the pan skin and fat side down. Let cook until dark golden brown-about 5 minutes. Season with salt and pepper.
Turn your duck breasts over and let the other side cook about 2 or 3 minutes more. Remove from pan and set in warm plates to set.
keeping the heat on your pan, add the marmalade to the hot duck fat, stirring until melted, then whisk in the orange juice concentrate. Cook until thickened and slightly sticky. Serve over the duck breast. This sauce goes well with carrots, too.