Honey Mustard Steaks With Grilled Onions

• 1 onion (red)
• 80 ml course dijon style mustard (grain)
• 22 ml honey
• 16 ml cider vinegar
• 16 ml water
• 2 gr parsley
• 1 ml pepper sauce (hot)
• 1 gr course grind black pepper
• 4 slices ribeye