There are a few ways to reheat steak. You definitely don't want to ruin that leftover steak by overcooking it after you took the time to cook it to the perfect temperature. 1. In the oven. Preheat the oven to 275℉. Warm the steak for 20 to 30 minutes in the oven. When the internal temperature reaches 110℉, take the steak out of the oven and pan-sear it to finish warming it up. 2. On the stovetop. If you are in a hurry, you can skip the prewarming in the oven. Add a little oil to a pan. Place the steak in the pan and flip it every 60 seconds until the internal temperature reaches 125 to 130℉.