If you haven’t already, set the beef out on the counter about an hour before you want to start cooking until it comes to room temperature.

Prepare the herb coating by mixing the olive oil, dijon mustard, coconut aminos, garlic, rosemary, and thyme together in a bowl until well combined. Set aside.

Cut the beef tenderloin in half so you’re left with two pieces of equal length. Fold the end with the long slim tail along the side of the thicker part. Use kitchen twine to hold the meat together about every 2 inches so each piece of tenderloin is a thick uniform shape.

Preheat the oven to 450 F. Pat each piece of meat dry with a paper towel. You want the beef as dry as possible to ensure a nice crispy outer layer. Season the meat with salt and pepper. Use your hands or the back of a spoon to massage it into the meat well.

Heat a large skillet on the stove over medium high heat with the olive oil. Once the olive oil starts to simmer and smoke a bit, place one of the beef tenderloin halves on the skillet and allow it to brown for 1 ½ - 2 minutes before flipping it over and allowing the other side to cook for 1 ½ - 2 minutes. Because the tenderloin is round, I like to quickly sear the sides that haven’t been directly on the skillet for about 10 seconds just to give it a slight brown too. Transfer the tenderloin to a plate and repeat this step with the other half. Remove the skillet from the heat.

Place the other tenderloin half back into the skillet so both are nestled in the skillet together. Use a pastry brush to brush the herb mixture onto the meat, making sure the tops and sides are well coated.

Insert a meat thermometer into one of the pieces of meat and place the skillet in the preheated oven for 10 - 12 minutes or until the meat has reached your desired temperature (see temperature notes below).

Remove the skillet from the oven and transfer the meat to a cutting board to rest for at least 20 minutes before slicing into ½ - 1 inch inch pieces to serve.