Pat the pork dry and trim away the sliver skin (the tough piece of membrane that is on one end of one side of the tenderloin). Trim away excess fat. Place the pork in a sturdy ziptop bag.
In a small bowl or liquid measuring up with a spout, stir together the marinade ingredients.
Pour the marinade into the bag, then seal the bag, removing as much air as possible. Move the bag around a bit so the pork is evenly coated, then place the bag in a shallow dish.
Marinade pork tenderloin for at least 2 hour or up to 1 day in the refrigerator. Let stand at room temperature 30 minutes prior to cooking. See Baked Pork Tenderloin, Grilled Pork Tenderloin, and Smoked Pork Tenderloin for three excellent ways to make pork tenderloin.
TO STORE: You can refrigerate unused pork tenderloin marinade in an airtight container or jar for up to a week.
TO FREEZE: Transfer the marinade to an airtight container or zip-top bag and freeze for up to 3 months. Thaw overnight in the refrigerator before using.