Method

1. For the caramelised onions, add oil to a frying pan over medium heat, then add the onions, season with salt, and cook for 20 minutes, turning, until golden. Add the sugar, red wine vinegar, another pinch of salt and freshly ground black pepper. Cook for 5 minutes until the liquid has slightly reduced. Cover with a cartouche and cook for a further 15 minutes until the onions have softened. To finish, add the butter and stir to combine.

2. For the parsley and spinach puree, add butter, eschalot and garlic to a frying pan over medium heat and sweat for 5 minutes until translucent. Add cream and reduce for about 3-5 minutes until thickened. Meanwhile, add parsley to a saucepan of salted boiling water. Cook, stirring for 2-3 minutes until the parsley starts to break up when rubbed between your fingers. Add the spinach and cook for a further 15 seconds. Drain into a sieve and sit the sieve in a bowl of iced water. Squeeze out all of the excess liquid from the spinach and parsley mixture and then place in a clean tea towel to absorb any water. Add the dry spinach mixture to the cream, stirring to combine. Place the mixture into a blender and puree until smooth. Season with salt and pepper.

3. For the pommes soufflé, pour oil into a saucepan or wok until it is one-third full. Heat the oil until it reaches 100-120°C. Pour oil into a second saucepan or deep-fryer until it is one-third full and heat to 185°C. Trim potatoes into rectangular cubes, 4 x 4 x 8cm, about 100g each and cut into 2-3mm slices. Lay slices on a clean tea towel to dry. Place potato slices into the saucepan set at 120°C. Gently and carefully shake the pan to aerate the oil. Cover your arm and hand with a tea towel to prevent splatter burns. Cook potatoes for 5-10 minutes until small bubbles appear over the surface of the slices. Transfer the slices to the deep fryer and quickly ladle hot oil over the potato slices continuously to assist in the puffing of the slices. Continue for 2-3 minutes until they puff up into pillows. Remove with a slotted spoon and drain on paper towel. Season with salt.

4. For the steak and kidneys, remove kidneys from the milk and pat dry with paper towel or a clean tea towel. Slice kidneys horizontally and open out kidney so it is flat on the board. Carefully remove the sinew in the centre of the kidney with the tip of a sharp knife. Place on a flat tray with the steak. Scatter garlic and thyme over kidneys and steak and season with sea salt and pepper, then drizzle with 1 tablespoon of the olive oil. Heat a char-grill pan over high heat and cook steak for 2 ½ minutes each side for medium rare. Set aside to rest for 2 ½ minutes. Cook kidneys cut side facing up for 1 minute, then turn and cook for a further 10-20 seconds. Remove to a tray to rest. Slice bread into 1 ½cm slices and brush with remaining oil. Press down on char-grill pan and toast until golden. Set aside.

5. To serve, slice kidneys into thin slices horizontally. Carve steak thinly across the grain. Drizzle toasted sourdough with a little oil and spread with some parsley puree. Top with slices of steak, kidney, garlic and halved onions along with the pommes soufflés.

Serves 4