adapted from Ree Drummond, The Pioneer woman
2 Tablespoons butter plus more for spreading on the bread
1 large onion, halved and sliced (I used a Vidalia onion)
1 1/2 pounds ground beef
5 dashes Worcestershire sauce (or more)
Salt and pepper
8 slices, thin sliced Rye bread (or Sourdough, English toasting, wheat, or any kind of bread you like)
8 slices Swiss cheese (Pepper jack would be good too or Provolone)
In a medium skillet, melt 2 tablespoons of the butter over medium-low heat. Throw in the sliced onions and cook slowly until the onions are golden brown and soft, 20 to 25 minutes, stirring occasionally.
In a medium bowl, mix together the ground beef, Worcestershire and some salt and pepper. Form into 4 or 5 patties.(I like to shape mine the same shape as my bread so I had rectangle patties)
In a separate skillet over medium heat, cook the patties on both sides until totally done in the middle, about 8 to 10 minutes (4 or 5 mintues per side).
Heat a clean griddle to medium heat (Or use another large skillet) To assemble and cook the patty melts, butter one side of bread, then place butter side down on the pre-heated griddle, then add a slice of cheese, hamburger patty, a spoonful of the cooked onions, another slice of cheese and another slice of bread. Butter the top of this last slice of bread. When it's golden brown on the bottom carefully flip the sandwich over, and let cook on this side until it's golden brown and the cheese is melted. Remove from griddle, slice in half and serve immediately!
If desired serve with Ketchup or mustard for dipping.... the onions really add to the flavor too.