To make the pickled cherries, put the cherry halves in a sous-vide bag with the remaining ingredients and cook in a water bath at 64°C (147°F) for 20 minutes. Put the bag in an ice bath immediately after cooking, then set aside until ready to plate.
To make the onion purée, put the butter in a medium frying pan over low heat. When melted and lightly foaming, add the onion and thyme and sweat over very low heat, until the onions are soft, ensuring there is no colouration. Purée in a blender until you have a very smooth white purée. Season to taste with the salt, lemon juice and pickled ginger juice.
To make the caramelised baby onions, cut away the green stem and peel the first layer of skin, ensuring that you leave the roots attached. Cut each baby onion in half. Put the olive oil and butter in a frying pan over medium heat. Sear the onions, sliced side down, charring them until they are golden black. Season heavily with fleur de sel. Make a dressing with the lemon juice, colatura and pickled ginger juice. Marinate the onions in the dressing at room temperature.
Season the beef generously with salt and pepper. Heat a frying pan over medium heat, add the grapeseed oil and sear the beef on all sides. Add the butter, thyme, rosemary and garlic and baste the beef until cooked to rare. Let the meat rest for 15 minutes before slicing. Season the beef with colatura.
To serve, reheat the onion purée and put a smear of purée on each plate with a slice of sirloin on top. Add a few pickled cherries and caramelised onions with some of the marinade. Coat the beef with the jus, season with fleur de sel, sprinkle with crumbled feta and finish with a few sprigs of samphire and mignonette.
© 2014 All rights reserved. Published by Murdoch Books.