For the Beef Patty (if making a burger):
- 1 lb (450g) ground beef (80/20 for juiciness)
- 1 teaspoon salt
- ½ teaspoon black pepper
- ½ teaspoon garlic powder
- ½ teaspoon Worcestershire sauce
For the Sautéed Mushrooms:
- 1 tablespoon butter
- 1 tablespoon olive oil
- 8 oz (225g) mushrooms, sliced (button or cremini)
- 1 clove garlic, minced
- ½ teaspoon salt
- ¼ teaspoon black pepper
- 1 teaspoon Worcestershire sauce
- ½ teaspoon thyme (optional)
For the Melt:
- 4 slices Swiss cheese
- 4 slices sourdough bread, brioche buns, or burger buns
- 2 tablespoons butter (for toasting)
- 1 tablespoon Dijon mustard or mayonnaise (optional, for spreading)