3. Cook the Patties:
In a bowl, mix ground beef with salt, pepper, and Worcestershire sauce. Shape into four thin, oval patties.
Cook in the same skillet over medium heat for 2–3 minutes per side until browned. Remove and set aside.

4. Assemble the Sandwiches:
Spread butter on one side of each bread slice. Layer bottom slices (butter-side down) with Swiss cheese, beef patty, caramelized onions, secret sauce, cheddar cheese, and top with remaining bread (butter-side up).

5. Cook the Patty Melts:
In a skillet over medium heat, cook sandwiches in batches until golden brown on both sides and cheese is melted, about 1–2 minutes per side.

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Storage

• Store leftover secret sauce in the fridge for up to 5 days.
• Assemble and cook patties fresh for best results; sandwiches are best enjoyed hot.