Rub the rosemary-garlic mixture on top and all along the sides of the beef. Arrange the sliced red onion on the bottom of the same skillet and place the seasoned beef tenderloin on top of the onions.

Herbs that complement beef tenderloin include rosemary, thyme and sage ... Afterward, remove the twine and slice into 1-inch thick pieces.

Add the sliced leeks ... add some herbs and spices to the gravy, such as rosemary, thyme, and sage. How long do I need to ...