Preheat the oven to 200C/400F/Gas 6.
For the steak, rub the steak with olive oil, heat a griddle pan until smoking hot and griddle the steak for two minutes on each side. Season well with salt and freshly ground black pepper, remove from the heat and leave to rest for five minutes. Slice thinly.
For the Italian-style roast potatoes, place all of the ingredients into a small roasting tin and roast in the oven, shaking from time to time to ensure even cooking, for 15 minutes, or until golden-brown.
For the spicy kale, heat the olive oil in a wok, add the onion and red pepper and fry until softened. Add the kale, chilli flakes, salt and freshly ground black pepper and fry until wilted slightly.
For the balsamic glaze, pour the balsamic vinegar into a small pan and simmer over a low heat until reduced by half and syrupy.
To serve, place the spicy kale onto a serving plate and top with the sliced steak. Serve the Italian-style potatoes on the side and drizzle over the balsamic glaze.
