Season steaks with salt and pepper and let come to room temperature, 10-15 minutes. Meanwhile, heat cast iron skillet on high flame for about 5 minutes. Sear steaks on first side for 2-3 minutes, then flip and add butter on top and let melt.Remove steaks from heat once they reach 10-15 degrees below desired temperature. Wrap in foil and let sit at least 5 minutes before serving.
Wash and peel the potatoes. Slice into desired fry length and thickness. I recommend about 1/4in thick for a skinny, crispy result. Place the sliced, uncooked fries into a large bowl. Cover with ice and fill with water. Let the potatoes chill in the water for at least 30min or up to an hour.
Fill a large, deep pot about 2/3rds the way full of oil and heat to 325 degrees. Remove fries from water and pat dry. Then carefully place into the hot oil. Depending on the size and depth of your pot, you might need to fry the potatoes in batches. Do not stir the fries once they are in the oil. Let them sit, if you stir, there is a good chance you will break the fries. Let the fries cook until they are slightly lighter than the color of a McDonald's french fry. The timing really depends on several factors like quantity of oil and potatoes, size of pot, etc. so timing is difficult to measure here.Once fries are just beginning to get golden, remove them using a spider strainer. Let them cool on a paper towel lined plate or wire cooling rack. Let the oil come back up to 350 degrees F.
Wait to do the second fry until you are ready to serve. Once the oil reaches 350 degrees F, return the fries to the pot for 1-2 minutes or until golden. You'll want to pull them out before they get too brown or they will be too crispy.Let the fries drain on a paper towel lined plate or rack. Season with salt while still hot. Serve immediately.
Whisk all the ingredients together until well combined.Do a little taste test and see if it needs more salt or horseradish depending on your preferences for salty and spicy!
Nutritional Values are only estimate and may vary.