The best way to know when the steak is ready is by inserting a thermometer. We take ours to about 130 degrees, by the time it carries over, it will be a perfect medium. If you like it cooked a bit more, continue cooking an additional two to four minutes.
Slice just before serving.
For the Frites
Pour oil into the pan, leaving room at the top for the potatoes when added. Heat the oil to 325 degrees F. (this temperature is very important)
Cut the potatoes about ½ inch wide and three inches long. Dry all the pieces thoroughly in a clean dish towel (removing water will keep the oil from splattering). Divide the raw fries into batches of no more than one cup each (do not fry more than one batch at a time to allow for even cooking and ensuring that your oil doesn't go down too far in temperature).
When the oil has reached 325, fry the potatoes for four to five minutes per batch. They should be lightly colored but not yet golden. If your fryer has a basket, simply lift it out the remove the fried potatoes. Otherwise, use a long-handled strainer to lift the potatoes out of the oil.
Bring the temperature of the oil back to 325 degrees F in between batches. The fries can rest for several hours at room temperature until you are ready to finish frying them to serve.
Again, heat the oil to 325 degrees F. Fry the blanched potatoes in one cup batches until they are golden brown and perfectly crisp, about two minutes. Drain on fresh paper towels placed in a large bowl or sheet pan. Sprinkle generously with salt and pepper and serve.
Unless you love sogginess, don't cover the potatoes. If you are so inclined to dip them in truffle aioli, please oblige.
Recipe by In Good Taste at https://ingoodtaste.kitchen/date-night-dining-classic-steak-frites/