Combine ground beef, breadcrumbs, egg, Worcestershire sauce, garlic powder, onion powder, salt, and pepper in a large bowl. Mix gently with your hands until just combined, because overworking the meat makes tough patties.

Divide the mixture into 4 equal portions and shape into oval patties about 3/4 inch thick. Press a shallow indent into the center of each patty with your thumb to prevent puffing during cooking.

Heat a large skillet over medium high heat with a tablespoon of oil. Sear the patties for 4 minutes per side until a beautiful brown crust forms. Remove patties to a plate and set aside.

Add butter to the same skillet and reduce heat to medium. Add sliced onions and cook for 8 to 10 minutes, stirring occasionally, until soft and golden brown.

Add mushrooms to the skillet and cook for 4 to 5 minutes until they release their liquid and turn golden. Stir in the minced garlic and cook for 30 seconds until fragrant.

Sprinkle flour over the vegetables and stir constantly for 1 minute to cook out the raw flour taste.

Pour in beef broth and Worcestershire sauce while whisking continuously to prevent lumps. Bring to a simmer and let the gravy thicken for 3 to 4 minutes. Season with salt and pepper to taste.

Nestle the seared patties back into the gravy. Cover and simmer for 8 to 10 minutes until the internal temperature reaches 160 degrees F. Let rest for 2 minutes before serving.