Only a real wood fire can produce the distinct aroma that comes from the rendered fat and juices that drip from a well-marbled cut of beef -- food scientists call it pyrolysis, but "fragrant, aromatic char" fits better. It's the scent of grilling, and you don't need a grill to get it. Simple is best when cooking over a campfire. Char thick, well-marbled steaks, such as ribeye and strip, with minimal seasonings -- unless you forage your own herbs. But safety first: Only build a fire where permitted, under minimal or no wind, and keep water or a shovel on hand if the flames get out of hand.
Build the fire, a little larger than the grate or cooking surface, using dry, aged wood. Hardwoods and fruitwoods, such as oak, peach and apple, work best. Scavenged green wood produces dark, distasteful smoke that essentially robs steaks of flavor by masking it. After the fire develops about 2 inches of ashy charcoal, push some of it to one side to make one end of the bed about 1 inch higher than the other -- you'll use the high side for searing and initial cooking and move the steaks to the low side to finish.
You can purpose just about any flat, heat-stable surface for cooking over a campfire -- but a grill rack works best. Outdoor grill racks are similar to what you use on a backyard grill but with legs. Simply set it over the charcoal bed. In lieu of a grill rack, set up the rack from a backyard grill. Line the perimeter of the charcoal bed with 4- to 6-inch-tall rocks and place the rack on them. You can also use a cast-iron skillet or Dutch oven to cook the steaks: Heat the skillet or Dutch oven directly on the coals for about 20 minutes before laying the steaks.
If you're really roughing it, you can use dry, flat river rocks -- but they must be completely dry or they'll explode, ruining your steaks, your evening and anything else in a 5-foot radius.
Steaks can sit out as long as two hours, but you only need them at about 70 degrees Fahrenheit when you start cooking. Just take them from the cooler when you have about 2 inches of charcoal burned down and let them sit off to the side. Season the steaks early, at least a couple hours ahead of cooking. Coat the steaks with oil if you like, though this isn't essential. Choose a good steak, season it well and build a hot fire -- you're ready to cook.
Cooking the steaks takes significantly less time than setting up the cooking area, but it ultimately depends on their thickness, the outside temperature, the humidity and the level of heat emitted from the charcoal.
Let the cooking surface heat for at least 20 minutes -- you need it screaming hot to develop a solid, charred sear on the steaks. Lay the steaks on the hot portion of the grate and sear them on each side for about 2 to 3 minutes, then move them to the cool side. Let the steaks cook for another 1 or 2 minutes for medium rare. Press the steak with your finger -- as a general rule, the firmer the steak the more cooked the interior.
Set the steaks off to the side of the heat and slather them with butter. Again, butter is optional, but for the effort, you should go all out. Let the steaks rest for about 5 minutes before serving them -- if you can stand the wait.