Whisk together the vinegar, salsa macha, olive oil, and shoyu in a medium bowl. Place the steak into a 1 gallon zip-top plastic bag and pour in the marinade. Gently massage the steak and marinade to coat evenly. Squeeze out most of the air, seal, and refrigerate for at least 1 hour and up to 4 hours.
Stir together the butter, salsa macha, lime zest and salt in a bowl. Lay out a sheet of plastic wrap and spoon the compound butter along the center of one edge of the sheet. Roll the plastic wrap around the butter and twist the ends to form a tight log. This can be made 48 hours ahead and kept in the refrigerator. Remove from the refrigerator an hour before serving.
Prepare a hot charcoal fire on one side of the grill, with a moderate fire, or even no fire, on the other half of the grill.
Remove the hanger steak from the marinade and allow it to rest on a cooling rack over a sheet pan while the grill is heating up. Discard the marinade.
Grill the steaks on both sides until golden brown and charred, about 4 minutes per side? Move the steaks to the cooler zone of the grill, close the lid and continue to grill until the meat reaches an internal temperature of 125°F on an instant read thermometer. Remove the meat to a cutting board
and let rest for 5 minutes.
Slice the steak across the grain and serve with compound butter and a sprinkling of Citrus Cilantro Jalapeño Salt.
