To create Tasty Slow Cooker Salisbury Steak Meatballs, follow these straightforward steps:

1. Prepare the Meatball Mixture: In a large mixing bowl, combine ground beef, breadcrumbs, chopped onion, milk, egg, garlic powder, salt, black pepper, and Worcestershire sauce. Mix well until thoroughly combined.

2. Form the Meatballs: Shape the mixture into meatballs, about 1-1.5 inches in diameter. Set aside on a plate while you prepare the gravy.

3. Make the Gravy: In a separate bowl, whisk together cream of mushroom soup, beef broth, onion soup mix, sliced mushrooms, and garlic powder until smooth.

4. Add to Slow Cooker: Pour the gravy mixture into the bottom of the slow cooker. Place the meatballs on top of the gravy in a single layer.

5. Cook: Cover the slow cooker and set it on low for 6-7 hours or on high for 3-4 hours, until the meatballs are cooked through and tender.

6. Serve: Once cooked, gently stir the meatballs in the gravy to coat them. They are ready to be served!

7. Garnish: If desired, sprinkle with chopped fresh parsley before serving for added color and flavor.

These simple steps will guide you in creating a hearty and delicious meal that satisfies everyone at your table.