Start by measuring out and prepping the ingredients listed. you'll find more tips and substitutions on the blog. There's several options for dairy free as well.
Next mash together the softened butter or dairy free option together with the garlic and minced fresh herbs. Set aside while you get the beef tenderloin ready.
Roast until an instant read thermometer comes to your desired doneness. Let the roast stand covered for 10 minutes before removing the kitchen twine and slicing.