Preparation Steps

• In a large bowl, combine the ground beef, breadcrumbs, milk, egg, chopped onion, Worcestershire sauce, salt, and pepper. Mix gently until just combined. Do not overmix.
• Divide the meat mixture into 4 equal portions and shape them into oval patties, about 0.75 inches thick. Make a slight indentation in the center of each patty to prevent them from puffing up during cooking.
• In a large skillet, melt 1 tablespoon of butter over medium-high heat. Brown the patties for about 3-4 minutes per side. Remove the patties from the skillet and set aside.
• Add the remaining 1 tablespoon of butter to the same skillet. Add the sliced mushrooms and chopped onion and cook until softened, about 5-7 minutes.
• Sprinkle the flour over the mushrooms and onions and stir well to combine. Cook for 1 minute, stirring constantly.
• Gradually whisk in the beef broth and Worcestershire sauce. Bring to a simmer, scraping up any browned bits from the bottom of the skillet.
• Return the Salisbury steak patties to the skillet. Reduce heat to low, cover, and simmer for 15-20 minutes, or until the patties are cooked through and the gravy has thickened.
• Season the gravy with salt and pepper to taste. Serve the Salisbury steak patties hot, topped with the mushroom gravy.