Pittsburgh Salad

Method

1. Cut 150 g of peeled potato into chips about 1 cm square and as long as the potato allows. Drop them into a bowl of cold water and soak 20 minutes to wash off surface starch, then drain and dry very thoroughly on a tea towel — wet chips will spit in the oil.
2. Pour the sunflower oil into a deep, heavy pan no more than half full and bring it to 160C. Blanch the chips for 4 minutes, until soft and pale with no colour, then lift out onto kitchen paper and let them cool while you cook the steak.
3. Pat 120 g of sirloin dry, rub it with 1 tsp of vegetable oil and season both sides generously with salt and coarse black pepper. Sear in a dry cast-iron skillet over high heat, 3 minutes a side for medium-rare (an internal 52-54C), pressing the fat edge onto the pan for the last minute. Move to a board and rest 5 minutes.