I have a quick and easy recipe that everybody loves - only 3 ingredients. Only takes 30 minutes to marinade and comes out amazing.
First off, get boneless Ribeye at 1.5 inches thick if you can. If you can get it at Costco even better. Their steaks are high quality - especially the Ribeye. If you can't get Ribeye get something thick and preferably with a little fat.
Here's the recipe for 2-4 steaks - enough to fit into a Gallon ziplock bag. I don't have exact measurements because I just pour this stuff in. You can adjust to your liking.
Put steaks in Gallon ziplock bag - make sure it's not a leaky one. Leave on counter.
Mix the following in a bowl or container. I usually use a 2 cup measuring cup.
Between 1 and 1.5 cups soy sauce
4 tablespoons of minced garlic - with the liquid.
Fresh ground pepper - 25 turns of pepper grinder.
1/2 cup or more water
Stir and pour into ziplock with steaks.
Remove as much air as possible. If steaks aren't immersed in liquid add a little more water.
Let steaks sit 15 minutes at room temp. Turn over and let sit 15 minutes more.
With 6-8 minutes left, turn your grill on high with cover closed. This should give it enough time to heat up to maximum temp. My grill gets over 600 degrees according to built in thermometer. You want it as high as possible.
Once grill is ready, use tongs or a fork and place on grill. Close cover immediately to lock in heat. Set your timer to 6 minutes. When timer goes off, flip over and close cover again. Set timer for 6 minutes. When timer goes off, take a meat thermometer and check the thickest parts of steak in a couple places. Keep doing this until meat temperature reaches 145 degrees - which is medium. Remove steaks and let them rest in a pan or plate for 5-10 minutes to seal in the juices. They will continue to cook while resting and you can get all the other stuff ready while you wait.
They end up being between medium and medium well so everybody is happy. If people like it done more than that, just buy crappy steaks and tell them to put A1 on them.
When grilling, I suggest keeping the lid closed to let the heat do it's thing. Otherwise, I feel it dries out what you are cooking easier. Also keep an eye on flare ups with this recipe since marinade will drip on your grill burners. Don't let your steak sit over a big flame and get charred too much. Move it and blow the flame out. Then put it back.
If you must cook it in an oven, I suggest preheating the oven to 450-500 and using a broiler pan. It may take longer to cook and not be as good but I've done it several times and it comes out very good - just can't compete with the grill.
This is a good base. You can add other stuff to your liking as well like garlic powder, minced onions or onion powder or even chili powder. But I found they get sort of lost in the strong flavors of soy sauce and garlic. But believe me, nobody will taste or even know you used soy sauce. It's almost acting as a brine but it penetrates the meat quickly and evenly.