Straccetti di manzo, which translates roughly from the Italian to “little rags of beef,” is a trattoria staple. The version we enjoyed at Armando al Pantheon in Rome inspired our riff on the dish. The cooking here is minimal and quick, making this ideal for a weeknight dinner, but the beef must be thinly sliced. We freeze the meat for about 20 minutes to firm it a bit, which allows a sharp knife to glide through the grain. After a quick sear in a hot skillet, the steak slices go directly onto a bed of peppery arugula and sweet-tart tomatoes. Balsamic vinegar, reduced as it deglazes the pan, and shaved Parmesan are the finishing touches. We prefer tri-tip steak for this recipe, as it has great flavor and a tender texture.