Pizza Spaghetti Pie

• 1 egg (beaten)
• 450 gr beef (lean ground)
• 230 ml pizza sauce
• 160 ml evaporated milk
• 110 gr mozzarella (shredded)
• 55 gr fine dry bread crumbs
• 45 gr spaghetti (cooked)
• 32 gr pramesan cheese (grated)
• 30 gr onion (chopped)
• 28 gr butter