- 1 1/2 pounds ground sirloin
- 3 ounces black truffle butter
- 1 teaspoon salt
- 4 slices pancetta
- 4 ounces Taleggio cheese, sliced
- 4 brioche buns, split in half and toasted
- 1 heirloom tomato, sliced
- 8 radicchio leaves
Preheat the oven to 350°F.
In a large bowl, combine the beef, truffle butter, and salt. Mix with a fork or your fingers until the butter is just incorporated. Form the beef into 4 patties. Lay a slice of pancetta over each patty.
Preheat a large, ovenproof skillet (preferably cast iron) over medium-high heat until hot. Put the burgers in the skillet, pancetta-side down, and cook for about 4 minutes per side for rare, 5 minutes per side for medium-rare.
Put the cheese on top of the burgers and place the skillet in the oven until the cheese is melted, about 5 minutes.
Place the burgers on the bottom bun halves, top with the tomato slices and radicchio, and cover with the top bun halves.