1/2 teaspoon hickory-smoked salt, sea salt, or Kosher salt
1/4 teaspoon chipotle chile powder, more to taste
1 teaspoon finely chopped fresh cilantro or flat-leaf parsley
1 pinch freshly ground black pepper, more to taste
1 splash vegetable oil or clarified butter
For the mustard butter:
2 tablespoons unsalted butter, at room temperature
2 teaspoons dry mustard powder
1 generous teaspoon Dijon mustard
Pat the steaks dry and rub them with the salt, chipotle powder, and cilantro. Refrigerate the steaks, uncovered, for at least 1 hour, or up to 8 hours. To make the mustard butter, mash together the butter with the mustard powder and the Dijon. Form it into two mounds and chill on a plastic wrap–lined plate. Heat a little oil or clarified butter in a grill pan or cast-iron skillet and cook the steaks over high heat, being sure to get a good sear on each side. For rare steaks, cook 5 to 7 minutes total on both sides, or aller-retour (“to go and return”). Remove the steaks from the pan and put on plates. Top each steak with a knob of the mustard butter and some ground black pepper and serve with a big pile of fries.