Skillet Hamburger Pie

• 6 instant mashed potato granules (servings)
• 700 gr beef (ground)
• 500 gr green beans (cut drained)
• 300 gr beef gravy
• 120 ml sour cream
• 60 gr onion (chopped)
• 50 gr celery coarsely (chopped)
• 40 gr american cheese (shredded)
• 7 gr chives snipped
• 5 ml worcestershire sauce