Salisbury Steak with Onion Gravy

Ingredients

1 lb ground beef

1/3 cup breadcrumbs

1 egg

1 small onion, finely diced

1 tsp salt

1/2 tsp black pepper

1 tbsp oil or butter

For the onion mushroom gravy

2 cups beef broth

1 cup sliced mushrooms

1 small onion, sliced

1 tbsp Worcestershire sauce

2 tbsp flour

1/2 tsp dried thyme