Step 1

In a large (gallon sized) zippertop plastic bag combine the red wine, balsamic, olive oil, shallot, garlic, mustard, tarragon, salt and pepper. Squish so that everything is blended, then slide in the steaks and turn them so that they are coated with the marinade.

Step 2

Seal the bag, pressing out excess air, and refrigerate the steaks in the marinade for 2 to 4 hours.

Step 3

Heat the grill to medium high. Grill the steaks for a total of 5 minutes on each side, flipping them a total of three times to get cross hatch marks on both sides, turning the steak ¼ turn for the last two flips, so that the grill marks will form and cross hatch on the other side.  Let sit on a cutting board for 5 to 10 minutes before slicing and serving.