Yield: 2 servings
- 9-10 ounces ground chuck (more or less, depending on the size of your bread)
- Kosher salt
- 1 small onion
- 4 slices of rye bread
- 2 ounces Swiss-style cheese (Gruyere or Emmentaler are my favorites) -- sliced thin or grated
- 4 tablespoons butter (or more), softened
2. Slice the onion thin. Heat about a tablespoon of the butter in a small skillet until it stops foaming and add the onion. Sprinkle with salt and cook the onions, stirring occasionally, until they're beginning to brown. Set aside.
3. Heat a cast iron or other heavy skillet to medium high heat.
4. While the burger pan heats, place a griddle or large skillet over medium low heat. Butter one side of each slice of bread and lay the slices, buttered side down, on the griddle. Distribute the cheese evenly over the 4 pieces of bread. Spread the onions over the cheese on two pieces of the bread -- not all 4, or final assembly is a mess.
5. While the bread begins to brown and the cheese melts, cook the beef patties however you like them. I think medium-rare to medium works best.
6. When the meat is done, remove the patties to the rack and let them rest for a couple of minutes. Place a patty on each of the slices of bread with onions and top them with the other slices. If you've timed it right, the sandwich should need just another minute or so on each side for the cheese to melt completely and the bread to turn deep golden brown.