Grease the interior of a 6-quart slow cooker with non-stick spray.
In a large mixing bowl, toss cubed steak and potatoes with onion, garlic, salt, pepper, paprika, and Worcestershire sauce until evenly coated.
Transfer the mixture to the slow cooker and spread into an even layer.
Cover and cook on High for 4 hours or Low for 7 to 8 hours until potatoes are fork-tender.
Sprinkle shredded cheddar cheese and bacon bits evenly over the surface.
Cover and cook for an additional 15 minutes until the cheese is completely melted.
Serve warm topped with a dollop of sour cream and fresh green onions.