Soak the cut potatoes in cold water for 30 minutes, then drain and pat dry.
Heat vegetable oil to 325°F (165°C) and fry the potatoes in batches for 3-4 minutes until pale and softened. Remove and drain.
Season the steaks with salt and black pepper on both sides.
Heat a heavy skillet over high heat and add olive oil. Sear the steaks for 3-4 minutes per side until golden brown and cooked to desired doneness.
In a small pan, melt the butter over low heat. Add minced garlic and cook for 1 minute before stirring in fresh parsley.
Increase the oil temperature to 375°F (190°C) and fry the potatoes again for 2-3 minutes until crispy and golden brown.
Slice the steak and drizzle with garlic butter. Serve with crispy fries on the side.