Season your Blackstone griddle if you haven’t already done so.

Remove the flank steak from the refrigerator, and let rest at room temperature for 30-45 minutes.

Preheat one side of the Blackstone to 450 to 500°F. Heat the other burner to low heat, around 300°F.

Pat the steak dry. Brush the oil on both sides of the flank steak, and season generously with salt and pepper.

Transfer the steak to the high-heat side of the griddle and sear for 3-5 minutes. Flip to the other side to sear for another 3-5 minutes.

Move the steak to the low-heat side of the Blackstone to continue cooking to your preferred level of doneness. The entire process usually takes 10-15 minutes for medium-rare.

Rest the steak at room temperature for 5-10 minutes. Slice against the grain to serve.