I'm in the food & wine business, and after 10 years of eating & cooking my way around the world, here is my method for producing the best home-cooked steak.
1. Buy 15-30 day, dry-aged, NY Strips, or Ribeye, from Bryan's Fine Foods in Corte Madera: http://www.bryansfinefoods.com/
. I'm not going to argue about Lobels or heaven forbid Omaha or whatever crap you can buy at Costco. If you are serious about steak, and want the very best, Bryan's Private Reserve aged steaks are where it is at. If you are wanting filet, get it from anywhere as frankly once you get to prime in filet, the differences are minimal & I find it doesn't work well for my method of steak preparation---though Bryan's filet tails are ridiculously good for an appetizer while you cook your steak.
2. Let the steaks come to room temp.
3. Heat up your oven, or preferably an outdoor grill, to 375-400 degrees.
4. Put your seasoned cast iron skillet in the oven to get hot. You'll need 1 skillet for every 2 N.Y. strips.
5. Turn on your burners, again preferably outdoors as you are about to generate a crap-load of smoke, as high as they will go.
6. Move the skillets from the oven to the burners. Let them get as hot as possible.
7. Once the skillets are as hot as possible, quickly season the steaks on both sides with your preferred salt & pepper seasoning. Personally I prefer McCormicks Montreal Seasoning as it is pretty basic & simple + avail nationwide. DO NOT USE OIL OR EVEN WORSE BUTTER! OIL BURNS & AFFECTS THE FLAVOR OF THE STEAK!
8. Gently lay the steaks on the skillets. Leave them alone for 2-3 minutes, depending on how much char you want.
9. Turn them over once, using tongs. Leave them on the skillet on the buner for about 1 minute, then quickly move the skillet into the grill/oven at 375 degrees.
10. Don't do anything else.
11. 3-4 minutes in the oven = rare. 4-6 = medium rare. 6-7 = medium.....and frankly overcooked. Do not cut into the steak to check done-ness---learn to use the touch method to determine wellness.
12. Immediately plate the steaks right out of the oven, again using the tongs. Do not cover them with aluminium foil.
13. If you prefer a bit of xtra richness, Whole Foods has a very nice butter-Blu Cheese or butter-Gorgonzola mix that works well---apply a small pat/smear of this over the top of your steak---thin is the key---you don't want it swimming in it. You could also use clarified butter or ghee. Do not use bacon fat or duck fat---it overwhelms the taste of the steak.
14. Let the steak rest for at least 10 minutes.
15. Eat & enjoy.
If you must have grill marks on your steak, the preferred method is to remove it from the skillet using tongs & put it on the grill for 1-2 minutes before removing. I'm not a fan of grill skillets as they don't seem to sear as well.
This method is fairly foolproof, and most importantly aside from some ribeyes or porterhouses, the chances of flame-ups are pretty low---I have two 20k btu outdoor burners that I use to heat the skillets & occasionally I will get some scattered flames during the searing portion of the procedure, but I've never had a flare-up once the skillet goes into the grill---a real problem when cooking ribeyes due to the high fat content.