Instructions
Follow the steps and taste along the way.
Prepare the leeks
Halve the leeks lengthwise and rinse thoroughly between the layers. Pat each half dry and cut it into pieces about 8 cm long.
Toast the hazelnuts
Toast the hazelnuts in a small dry pan over medium heat for 3 to 4 minutes. Shake the pan occasionally; once they become fragrant and dark spots appear on their surface, transfer them to a plate. Roughly chop once cooled.
Brown and braise the leeks
Heat the olive oil in a large pan over medium-high heat. Place the leeks cut side down and cook for 4 minutes, until golden-brown patches form. Turn them over and add the butter, water, salt, and black pepper. Cover and braise over low heat for 12 to 15 minutes, until a knife slips easily into the leeks but they still hold their shape.
Finish the mustard jus
Transfer the tender leeks to a warm plate. Stir the Dijon mustard and apple cider vinegar into the juices in the pan. Stir over low heat for 1 to 2 minutes, until the jus comes together and thickens slightly. Taste; it should be salty and buttery, with a bright acidity.
Serve
Pour the mustard jus over the leeks. Sprinkle with the chopped hazelnuts and chives, and serve warm.



