Cooking juicy beef in a pan

Question

I recently cooked beef in a pan, and it came out pretty leathery. I came to cooking.SE to find some advice, and found this:

"The cut is important for both techniques. For sauteing, you need a lean cut - fillet, sirloin, or good rump steak. These should be cooked quickly over a high heat" from Cooking beef: how to make it tender? (most of the advice on the page seems to be "high-heat low-time")

My question is for a bit more follow-up on this. Most importantly, how will I know that the beef is cooked well enough to be safe, without it losing its tenderness? Also if it makes any difference, I'm using a non-stick pan (cooking it in olive oil is okay?)

Answer

The best way to test if it's done is to use an instant-read thermometer. Slide it into the thickest part, away from any bones. I like to lift up the meat with tongs and poke it into the edge, all the way to the center. You're looking for about 135-140F for medium rare; take it off a little early if anything because the temperature will go up a bit once it's off the heat. Let it rest for ten minutes or so before digging in to let the juices re-distribute.

I don't like using nonstick for steak, or olive oil. Neither does well at high heats, which is what you need to cook off moisture at the surface and get a nice browned outside before the inside gets overcooked. Cast iron and steel (stainless or carbon) both work very well in my experience. For fat, use a high smoke point oil like safflower oil, or clarified butter.

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