Grill no lid over a hot bed of coals flipping as needed until done to your liking.
Are yours real thin; like 3/8"-1/2"?Got some of those from my FIL. They take to most styles of cooking, just do it HOT AND FAST!
Searing over a chimney woulda worked but I had 4 of them and also cooked some shrimp in a cast iron pan on the grill.
I'd say it turned out much better than I expected. I did a dry brine at room temp for a couple hours then just did monteral steak seasoning. After removing from grill I put a slab on homemade herbed butter. On top is a onion/mushroom/red wine reduction.