How to pan sear a thin steak?

I would actually recommend the opposite of what was said above. Since the meat is so thin you may have much better results pan searing it in an extremely hot pan from slightly frozen. This way the outermost layer will start to undergo the maillard reaction long before the inside of the steak reaches a medium-rare temp and will give you a better chance of preventing it from overcooking.

This link provides an overview of the process for a much larger piece of meat then your using but the searing process is what your concerned most with since your steaks are so thin. You will likely have to play with the timing a little bit with regards to how frozen the steak needs to start out but I figure erring on the side of too frozen is best since you can then heat them in the oven to the internal temp your looking for.

http://www.thekitchn.com/for-the-perfect-steak-first-freeze-it-solid-then-cook-for-an-hour-165793

1. Let the pan be as hot as possible, add meat just before the oil starts to smoke.

2. Make sure the meat is NOT wet, dry it, water will steam before you get the steak to look nice, making that steam will reduce the temperature in the pan and not enough heat is left to make the steak look nice.

3. Do not put to much stuff in the pan, do only one or two steak at a time, do not fill the whole pan.

4. Use a pan with lots of 'thermal capacity' i.e. a heavy/thick iron pan, not a thin pan. This means that you have lots of heat stored in the pan and it will not get cold so fast.

How to get the steak to look good?

Two tips –

1 Don't use butter.

2 Flash-fry it.

Flash frying is cooking very quickly in very hot oil. Given the thickness of your steaks and that you want them medium-rare the whole process happens very quickly.

On a high heat sear/seal one side, turnover and seal the other side, turn the temperature down and cook till medium-rare, the whole process really should only take minutes.

Don't use butter to fry them in. At the temperature you require to flash-fry butter will burn. Use a higher temperature oil such as vegetable, corn or nut.

If you want the absolute hottest temperature, I suggest using a charcoal grill if you have one.

The pan might be simply conducting too much heat into the thin steak to brown the outside before the inside is finished. Charcoal is a slower application of heat, and works by radiative heat instead of conductive. While such a grill can be a luxury, the broiler in your oven may have the same effect. Put the steak in a cool pan, toss under the broiler, and flip when its brown.

I cooked my thin rib eye steaks on a porcelain pan. I added butter and I cooked the steaks for 1 minute and 15 seconds per side over a medium flame. Adding salt and pepper were my only spices. My steaks tasted fantastic!