Old-Fashioned Salisbury Steak with Rich Mushroom Gravy

Ingredients:
For the Salisbury Steaks:
1 lb ground beef
1/3 cup breadcrumbs
1 egg
2 tbsp ketchup
1 tbsp Worcestershire sauce
1 tsp onion powder
1 tsp garlic powder
Salt and pepper to taste
For the Mushroom Gravy:
2 tbsp butter
1 tbsp olive oil
1 small onion, thinly sliced
8 oz mushrooms, sliced
2 tbsp all-purpose flour
2 cups beef broth
1 tbsp Worcestershire sauce
Salt and pepper to taste

Instructions:
Make the Patties: In a bowl, combine ground beef, breadcrumbs, egg, ketchup, Worcestershire sauce, onion powder, garlic powder, salt, and pepper. Shape into 4 oval patties.
Cook the Patties: Heat olive oil in a skillet over medium heat. Brown patties on both sides for 2-3 minutes per side. Remove and set aside.