I hear this all of the time! I would buy one of those amazing Tomahawk steaks, but I don't know how to cook it. Well, if this is you. here you go!
Cooking on Direct and indirect heat is key when cooking steaks like the the Tomahawk and the cowboy ribeye's. These steaks are over and inch to two inches thick and getting them cooked right demands two temperature zones.
I like to cook on charcoal, but this can be done on a pellet grill, or gas grill just the same.
Start buy taking the steak out of the fridge and letting it acclimate or come up in temp from the average cool temperature of the refrigerator. This actually relaxes the molecules and allows for the direct heat to penetrate further into the meat and allows for less indirect heat when cooking.
I start by covering the steak in garlic olive oil, not necessary, but the oil helps the seasoning adhere. I like to season my steaks with cracked black pepper and sea salt or kosher salt. With a grill at 450 degrees place on the grates vertically for 4 minutes. After 4 minutes of searing turn the steaks horizontally on the grates without flipping for an additional 4 minutes. This creates the perfect grilling marks!
After repeating this for both sides, remove the steak and temp it. The perfect Medium rare steak should temp between 125 and 132 degrees. This is lower than the recommended beef cooking temperature. Most likely your steak will be around the 100 degree mark, if so, reduce the cooking temp of the grill to 300 degrees and add back to the grill. Temping is the key and do not over cook!! The steak will increase by 1 to 2 degree after removing from the heat.
Next, after removing from the grill, let your steak rest for 15 minutes. This is a must! this lets the steak come down in temperature gradually and keep the juiciness in the steak and not all over your cutting board.