Rib eye, no question. Look for one with a larger marbled cap, the part that wraps around the edge.
Dry the steak. Kosher salt and black pepper. Throw on a hot grill. Rotate 30 degrees after 3-4 minutes and cook for another 3-4 minutes (depending on grill temp). Dry before flipping (especially if on a pan) and repeat. Only use the lid if it's 2"+. Shoot for medium rare, unless you're a cretin.
Let it rest for 5 minutes. Slice into 1/2" slices across the grain, something about that really opens up the flavor.
A cast iron grill pan (with ridges) is the jam if you are cooking indoors. You can get diamond grill marks on both sides