- In a bowl, combine all the ingredients.
- Rub the beef with half the herb salt. Season with pepper on all sides and let the meat rest at room temperature. Meanwhile, prepare the balsamic reduction.
- In a saucepan, reduce the vinegar by two thirds, about 15 minutes. Remove from the heat and set aside.
- In a ridged skillet over high heat, sear the beef in the oil on one side (you can also do it on the grill, without any oil).
- Reduce the heat to medium and cook for about 8 minutes per side for medium-rare.
- Thinly slice crosswise. Drizzle with the balsamic reduction and serve with Mashed Potatoes with Olive Oil.
If you use quality balsamic vinegar, 8 years of age or older, use it as is: it will be syrupy enough to not have to be reduced.