Double Bacon Swiss Mushroom Melt with Beef and Cheese

Ingredients

• 10 slices beef bacon, divided
• 12 oz (340 g) cremini mushrooms, sliced
• 1 tablespoon olive oil, if needed
• 1/4 teaspoon kosher salt
• 1/4 teaspoon black pepper
• 2 lb (900 g) 80/20 ground beef
• 2 large eggs
• 3/4 cup (45 g) panko breadcrumbs
• 1/2 cup (120 ml) milk
• 1 tablespoon Worcestershire sauce
• 1 tablespoon Dijon mustard
• 1 teaspoon garlic powder
• 1 teaspoon onion powder
• 1 teaspoon kosher salt
• 1/2 teaspoon black pepper
• 6 oz (170 g) Swiss cheese, 3 oz chopped and 3 oz sliced
• 1/3 cup (80 g) ketchup
• 1 tablespoon brown sugar
• 1 teaspoon Worcestershire sauce
• 1 tablespoon chopped fresh parsley, for serving