Place peppercorns in a plastic bag and mash them with the flat side of a meat mallet or rolling pin until finely crushed. Season both sides of steaks with salt and add to bag with crushed peppercorn melange. Refrigerate up to 48 hours. When ready to cook, heat oil in a large skillet over medium heat. Add steaks and cook 2 minutes per side, until browned. In a small bowl, mix together orange marmalade, onions and Worcestershire sauce. Add mixture to steaks and bring to a simmer. Simmer 5 minutes, until sauce thickens and steaks are cooked through.