Welcome to one of this country’s most delicious unknown sandwiches, the Beef on Weck. This simple but brilliant creation features thinly sliced, horseradish-covered roast beef piled high on a freshly baked kummelweck roll. When you add a steaming ramekin of fresh beef jus for dunking, you’ll understand why this is the pride of Western New York (sorry, chicken wings). Serve with chips or fries and pickles on the side.
Season beef with salt and black pepper.
Heat oil in a large skillet over medium-high heat. Cook beef roast in hot oil until browned on all sides on each side, 4 to 5 minutes per side. An instant-read thermometer inserted into the center should read 125 degrees F (52 degrees C). Transfer beef to a plate to rest.
Remove skillet from heat and whisk flour into skillet until flour taste cooks off, about 1 minute. Pour cold beef broth into skillet; place skillet over medium-high heat. Stir balsamic vinegar, black pepper, and any accumulated juices from the roast beef plate into beef broth mixture; cook until jus reduces slightly, about 5 minutes. Season with salt.
Slice sirloin as thinly as possible against the grain. Pile meat onto the base of each roll. Spread a thick layer of horseradish on the top bun and place top bun over meat. Serve with jus for dipping.
Per Serving: 388 calories; protein 46.1g; carbohydrates 17.9g; fat 13.5g; cholesterol 79mg; sodium 817.1mg.