In a large bowl, combine the ground beef, breadcrumbs, egg, grated onion, ketchup, Dijon mustard, Worcestershire sauce, garlic powder, onion powder, oregano, salt, and pepper.
Mix just until combined, then shape into 4 oval patties.
Brown the Patties
Heat olive oil in a large skillet over medium-high heat.
Cook the patties for 3–4 minutes per side until browned. They don’t need to be fully cooked yet. Transfer to a plate.
Onions & Mushrooms
Reduce heat to medium and melt the butter in the same skillet.
Add the onions and mushrooms and cook for 8–10 minutes, until softened and golden.
Stir in the garlic and cook for 30 seconds.
Make the Gravy
Sprinkle the flour over the mixture and stir for 1 minute.
Slowly whisk in the beef broth, then add the Better Than Bouillon and Worcestershire sauce.
Simmer for a few minutes until the gravy thickens.
Finish Cooking
Return the patties to the skillet along with any juices.
Spoon the gravy over the top, cover, and simmer for 10–12 minutes, until cooked through.