Combine softened butter, minced garlic, diced Fresno pepper, honey, lemon juice, kosher salt, black pepper, and chopped parsley in a heat-safe mason jar. Leave 1-2 inches of space at the top.
Light a small piece of natural lump charcoal until completely red-hot and lightly ashed over. Using tongs, place the hot coal into the mason jar on top of the butter mixture. Immediately seal the lid tightly.
Let the jar sit closed for 1-2 minutes to infuse the butter with charcoal smoke. Open the jar, remove the coal with tongs, and stir the butter until smooth. Set aside.
Pat the steaks dry with paper towels. Coat lightly with olive oil or beef tallow. Season generously with coarse kosher salt, black pepper, and garlic powder on all sides. Let rest at room temperature for 20-30 minutes.
Preheat your grill to 500-600 degrees for direct high-heat cooking. Sear the steaks for 2-3 minutes per side until the internal temperature reaches approximately 118 degrees and a deep, caramelized crust has formed.
Lower the grill temperature to 250 degrees or move the steaks to indirect heat. Close the lid and cook until the internal temperature reaches 125 degrees for medium-rare, about 10-20 minutes depending on thickness.
Remove the steaks from the grill. Spoon the coal-smoked Fresno honey garlic butter generously over the top. Rest for 10 minutes before slicing.
Slice the meat away from the bone, then cut against the grain into half-inch-thick pieces. Spoon any remaining butter and board juices over the sliced meat and serve immediately.