Here you will learn how to make an easy Pork Tenderloin with Honey Dijon Mustard. To make a delicious pork tenderloin with Honey Dijon Mustard, do the following: You will need a pork tenderloin, French fried onions, garlic and pepper. Add a whole container of French fried onions to a plastic bag, add 1/4 teaspoon pepper and 1/2 teaspoon garlic and crush the ingredients in the bag. Add some Grey Poupon mustard to your tenderloin, covering the entire meat. Sprinkle the contents of the bag all over the top of the meat. Bake at 400 degrees for about 30 minutes.