- Preheat oven to 375°F and grease a 9x13-inch baking dish. 
- Mix ground beef, onion, garlic, breadcrumbs, eggs, ketchup, Worcestershire sauce, and seasonings in a large bowl. 
- Press mixture into baking dish and bake for 20 minutes. 
- Boil potatoes until tender, then mash with butter, milk, and sour cream. 
- Drain grease from meat layer and spread mashed potatoes evenly on top. 
- Add cheddar cheese and bacon over potatoes. 
- Bake another 20–25 minutes until cheese melts and bubbles. 
- Let rest for 5–10 minutes, top with green onions, and serve.