Vegetarian Salisbury Steak

Ingredients (13)

• + 1 large onion, halved add to pantry
• + 1 ½ (12 ounce) packages meatless ground beef substitute (such as Impossible™ Foods) add to pantry
• ✓ ¼ cup bread crumbs
• ✓ 1 large egg
• + 1 tablespoon garlic powder, divided add to pantry
• + salt and ground black pepper to taste add to pantry
• ✓ salt and ground black pepper to taste
• + 1 tablespoon olive oil, divided add to pantry
• + 1 cup sliced fresh mushrooms add to pantry
• + 1 ¾ cups vegetable broth add to pantry
• + ¼ cup ketchup add to pantry
• + 1 tablespoon vegan Worcestershire sauce add to pantry
• + 2 tablespoons cornstarch add to pantry