Start with a thick cut steak to serve at least two.
With a thick steak you can have it all, a nice tasty sear on the outside and big fat juicy pink center on every slice. You simply cannot achieve this with a scrawny steak.
If possible, let the steak warm up to room temperature, covered of course, for a few hours before you cook it. The less heat you have to “push” into the meat, the better. Starting with an ice cold steak is not ideal.
Ignore all advice about lean or “healthy” meat. There are plenty of low fat opportunities in life, steak is not one of them. Marbling (Fat) is your friend, the key to tenderness and flavor.
The only seasoning you need is salt and pepper. Use plenty, and season the meat just as you start to cook it, not before. If you salt it too early it will start to “cure” and draw moisture from the meat! Never marinate a good piece of meat unless you want it to taste like salad dressing. Cooking a soggy marinated piece of meat is a fool’s errand. It will not sear and seal correctly.
For perfect flavor, sear the meat on all sides over very high heat until a rich dark brown color, avoid char unless you really like the burnt bitter flavor that comes with it. You can cook it in a pan with a little oil, or on a really hot grill. Unless you have a really hot grill with a good heavy grate, stick to the pan. BBQ grills with thin wire grates will never produce a good sear.
Do not squirt water on your embers to reduce flare ups, move the meat around to avoid direct prolonged flame contact.
To that end, don’t try to cook too many steaks on too small a grill.
Rest. The single biggest factor in a perfect tender juicy piece of meat, from single steak to a 25 pound Turkey, is rest. The general rule of thumb is 50%. Once you have a good understanding of this concept and a little practice, you will nail meat every time. If you roast a pork loin for 20 minutes, it needs to rest another 10 to finish cooking before you slice it. Let’s use the steak as an example. After we sear the steak heavily on all sides, if we were to slice it immediately, we would see that the outside was hot, gray and well done, while the center was dark red, nearly raw. It would be tough and juice would run all over the cutting board. If allowed to rest, standing on edge so it doesn’t continue to stew in its’ own juices, the temperature of the meat will even out from the edge to the center.
As the temperature evens out, proteins that have dissolved and degraded while cooking thicken the juices, the fibers relax and “Voila”, a juicy tender perfectly pink piece of meat from edge to edge, nice and warm in the center. With a thick steak I find the best thing to do is actually sear it, let it rest and then warm it back up in a hot oven for a few minutes before slicing and serving.