For the beef tenderloin:

1. Prep the tenderloin & season. Preheat the oven to 425°F. Remove the tenderloin from the fridge about 1 hour before cooking to reach room temperature. Trim any tendrils of fat or leftover membrane (any silver skin) off the tenderloin. Then pat the tenderloin dry with a paper towel. Cut the tenderloin in half crosswise- this will ensure the length of the tenderloin fits in the skillet. Then secure the tenderloin with kitchen twine if it isn’t already. 
2. Mix the spices. In a small bowl, combine salt/pepper- to taste, oregano, tarragon, rosemary, thyme, onion powder, garlic powder, and cumin. Stir the spices together to fully combine. Reserve about 2 teaspoons of the spice blend and set aside. Drizzle 1 tablespoon of oil over the tenderloin and rub to fully coat. Then sprinkle the remaining spice blend over the tenderloin and use your hands to massage the spice blend into the tenderloins until evenly coated. Then set aside.
3. Prep the glaze. In another bowl, combine 2 tablespoons of olive oil, maple syrup, worcestershire, and dijon mustard. Whisk the mixture together to combine and then set aside until called for.
4. Sear tenderloin & glaze. In a large cast-iron skillet (about 11 inches or larger), heat 2 tablespoons of oil over medium-high heat. When the oil is shimmering, working in batches, sear the tenderloin until golden brown on all sides, about 2-3 minutes per side. Note: at this stage, you aren’t cooking it through, just searing nicely to lock in moisture and bring out more flavor by caramelizing the outside. Then set the tenderloin aside and repeat the process with the other tenderloin, adding more oil to the skillet if your pan looks dry. After browning, remove from heat and place both tenderloins in the skillet and brush the prepared glaze mixture over the tenderloins, coating all surfaces.
5. Roast the tenderloins for 20-25 minutes, flipping them at the halfway mark. Cook until the tenderloins reach about 120° – 130°F when checked using a digital meat thermometer or probe for doneness- this temperature range will achieve a medium rare to medium consistency. This is optimal for beef tenderloin as you do not want to overcook such a pricy cut of beef. However, feel free to continue cooking to your desired level of doneness. Then take the beef out of the oven and transfer it to a cutting board to rest while you prepare the cream sauce.

For the warm horseradish cream sauce:

1. In a saucepan or skillet, heat the butter over medium heat. Once melted, add garlic and stir until dissolved and fragrant, about 1 minute. Add heavy cream, dijon mustard, lemon juice, and vinegar and stir until well combined. Let the cream mixture come up to a gentle simmer, and then remove it from heat. Then add the horseradish and reserved spice blend (from the tenderloin instructions in step #2, above) and stir until well incorporated. Let the sauce sit for at least 5 minutes before serving.
2. Serve. Remove the twine and slice the tenderloins into 1-2-inch thick slices and place them on a large platter to serve up family-style. Spoon the warm horseradish cream sauce over the slices or simply serve it on the side. Serve the beef tenderloin immediately alongside your favorite side items like mashed potatoes or veggies. Enjoy!