Mom's Best Meatloaf

• 1 egg (slightly beaten)
• 1 onion fine (chopped)
• 1 additional ketchup
• 700 gr beef (ground lean)
• 240 ml milk
• 80 gr soft bread crumbs
• 16 ml ketchup
• 8 gr green pepper fine (chopped)
• 5 gr prepared horseradish
• 4 gr salt