Remove flat iron steaks from the refrigerator for one hour before grilling to bring the temperature up.
Combine the olive oil, herbs and salt and pepper in a small bowl.
Coat the steak with the herb mixture, making sure to cover the sides and ends too.
Place on the grill for 4-5 minutes.
Turn it over and grill for another few minutes until to reach the desired internal temperature.
I recommend removing it from the grill when it is two to three degrees cooler than your target. Bring it inside and cover with an aluminum foil tent. This will let the steak rest, trap the juices inside, and the temperature will come up to your target.
Notes
Remove Steaks from Refrigerator Early: Always remove the steaks from the refrigerator ahead of time so they can come to room temperature. This helps them start to cook immediately when they hit the grill grate.Temperature of Steak: Remove the steaks a couple degrees ahead of the temperature you would like to end at, bring the steaks indoors and tent with foil for 5-10 minutes to allow the juices to stay inside the steak and not run out on the plate. During this time, your steak will continue to cook those extra 2-4 degrees.
Rare: 120 to 130 F; 5 & 3 minutes per side; remove at max 125 F
Medium-Rare: 130 to 135 F; 5 & 4 minutes per side; remove at max 130 F
Medium: 140 to 150 F; 6 & 4 minutes per side; remove at max 145 F
Medium-Well: 155 to 165 F; 7 & 5 minutes per side; remove at max 160 F
Well-Done: 170 F or more; 12 & 10 minutes per side; remove at max 165 F
Storage: You can store in a sealed container for up to three days in the refrigerator.Temperature Control: This steak is a little thicker and you don't want to have an undercooked inside when the outside is over done. If a steak is thin, go for a higher temperature. If you know you want a medium rare steak, go for a higher temperature, even if it is a little thicker. It's a balancing act. If you aren't sure you would like it, try it with one steak and practice.