The basics
I find that there are two keys to getting a grilled steak done perfectly:
- Get it dry.
- Get the temperature exact.
A lot of people recommend better quality cuts. They are right. The better the cut, the tastier it is. But it's not a definitive factor.
I've produced some awesome steaks daily, with the cheapest steaks, cheapest seasonings, and in a $20 frying pan. By awesome, I mean steaks that exceed the quality of many dedicated steakhouses using expensive cuts and thousand dollar grills (but I don't live in a steak country so steakhouses here aren't that good).
If the steak is wet, you'll end up steaming instead of grilling it. Less 'crunchiness' on the outside.
Cooking involves a lot of chemistry. I'm sure you're familiar with how water boils at 100 C and freezes at 0 C. Meats are like that too. Proteins in the meat change form after a certain temperature is reached, but stays that way no matter how much heat you put into it. So even if you leave a steak in the oven at 65 C for 24 hours, it won't burn. That's how sous-vide cooking works. If you want the detailed science, Amazing Ribs has a very concise yet informative article on this.
Past 70 C it becomes tough. Below 63 C, parasites can still live. (Yes, that includes anything below medium). Here's a guide to the temperatures on getting everything perfect.
Medium well is about 68 C. I personally prefer medium, at about 60-63 C. Apparently the American medium-rare is at 57 C. These are very narrow gradations in temperature - you can literally overcook your steak in a minute. That's why you get a thermometer. I make do with a really cheap analog latte thermometer. They're cheaper than grills and far more effective.
How to cook a perfect steak
- Get some paper napkins and really dry it down until there's no moisture.
- Dry brine your steak for about an hour before cooking. Wrote this up to explain dry brining. Basically just add salt and pepper and put it in the fridge.
- Take it out of the fridge. Don't wash off your seasoning but keep it dry.
- Put fat all over your steak. I recommend grapeseed oil because you can taste the 'true' flavor of your steak that way. Ghee is great too. Don't use butter because it burns too easily. Most vegetable oils work, experiment!
- Set your grill/stove to medium-high.
- Cook it on one side. Get the temperature up to about 55 C.
- Flip it over. If possible, flip it over only once. Wait for temperature to get to 68 C. Bring to plate.
- Eat it. Add BBQ sauce or whatever seasoning, but if you followed these steps right, the steak would have been so delicious that you wouldn't want to add anything on it.
More tips
Learn to sear the steak just right. The right sear should be brown on both sides (not grill mark black!). This takes quite a bit of skill and timing, and possibly more expensive equipment. Most people can only sear one side well, but that's ok.
Don't bother with grill or burn marks. They look nice but I've never tasted a great steak with grill marks.
Never cut a steak to see if it's done. Colors will change when exposed to air and the often poor lighting of smoke above a grill or frying pan. And you'll lose a lot of the juices while trying to cut it enough to see what it looks like inside.
Poke your thermometer on the thickest bit of steak. Or the part furthest away from the heat if you use a cheap pan/grill.
You can oven cook steak too, but I find that it's much more effort unless you're feeding a lot of people. Sear it before putting it into the oven, as many have recommended.