Preheat oven to 425°F. Pat steaks dry with paper towels, then season both sides with the kosher salt and pepper. Set aside allowing the steaks to come to room temperature for 30 minutes.
Heat the vegetable oil in a large cast iron skillet on medium-high heat until shimmering. Add the steaks and cook without moving or turning for 3 minutes. Flip the steaks over using tongs and immediately put the skillet in the preheated oven.
Cook until the steaks are firm to the touch, about 8-9 minutes for medium rare. You can check with an instant read thermometer to be sure. The steaks should be 130 degrees but will continue to increase in temperature by about 5 more degrees while resting. Remove from the oven and transfer the steaks to a warm plate. Tent with foil and keep in a warm location while preparing the sauce.
Return the cast iron skillet to the stove top set to low heat and add the butter. Once melted, add the shallots. Cook, stirring frequently, about 1 minutes. Carefully add the red wine, if using, and bring to a boil. Cook and stir, scraping up any browned bits stuck to the bottom, until the wine has mostly evaporated. Stir in the mustard and increase the heat to medium-high.
Add the beef broth and Worcestershire sauce and bring to a boil. Continue to cook and stir until the sauce is slightly reduced, about 5 minutes.
Turn the heat to medium and add the cream. Simmer for a few minutes or until the sauce coats the back of a spoon, about 3 minutes. Turn off the heat and stir in the herbs.
Transfer the steaks to individual plates and pour any accumulated juices from the steaks into the pan sauce. Stir to combine, then drizzle over the steaks and serve immediately.