Steak with Shoestring Frites
- 1 porterhouse steak (2 to 2 1/4 inches thick)
- Coarse salt and freshly ground pepper
- 1 large russet potato, peeled
- Safflower or peanut oil, for frying
Season steak generously with salt and pepper, and let stand at room temperature for 30 minutes.
Using a mandoline fitted with a fine julienne blade, julienne potato. Cover potato with cold water, and let stand for 20 minutes. Rinse, then drain and spread on paper towels to dry.
Heat a grill pan over medium-high heat. Cook steak, flipping once, until internal temperature reaches 125 degrees on a meat thermometer for medium rare, about 10 minutes per side. Transfer to a plate, and let rest for 10 minutes.
Meanwhile, heat 4 inches of oil in a wide, heavy pot until it registers 380 degrees on a deep-frying thermometer. Working in batches, fry a handful of potatoes in oil until golden brown, 1 to 2 minutes. Using a slotted spoon, transfer to paper towels to drain, and immediately sprinkle with salt. Thinly slice steak against the grain, and serve topped with shoestring potatoes.