Step 1

In a medium skillet, melt 2 tablespoons of butter over medium-low heat. Throw in the sliced onions and cook slowly for 20 to 25 minutes, stirring occasionally, until the onions are golden brown and soft.

Step 2

In a medium bowl, mix together the ground beef, salt & pepper, and Worcestershire. Form into 4 patties.

Step 3

Melt 2 tablespoons butter in a separate skillet over medium heat. Cook the patties on both sides until totally done in the middle.

Step 4

Assemble patty melts this way: Slice of bread, slice of cheese, hamburger patty, 1/4 of the cooked onions, another slice of cheese, and another slice of bread. On a clean griddle or in a skillet, melt 2 tablespoons butter and grill the sandwiches over medium heat until golden brown. Remove the sandwiches and add the remaining 2 tablespoons of butter to the skillet. Turn the sandwiches to the skillet, flipping them to the other side. Cook until golden brown and crisp, and until cheese is melted.

Step 5

Slice in half and serve immediately!