Sous vide portobello mushrooms, caramelised celeriac, remoulade and thyme

Preheat the waterbath to 70˚C

To begin, place the Madeira in a pan over a high heat. Add the thyme and allow to reduce for about 5 minutes until lightly syrupy. Whisk in half of the unsalted butter until creamy and glossy and set aside

For the mushrooms, peel the outside layers and remove the stalks. Grate the garlic into the Madeira reduction using a microplane, season the mushrooms and place in a vacuum bag along with the emulsion. Seal in a chamber (at 50% compression only so as not to crush the mushrooms) and cook for 1 hour. You may need to weigh the mushrooms down slightly as they will contain a fair bit of air

While the mushrooms are cooking, peel the celeriac and cut into a nice large cube shape. Thinly slice the cube, then slice again into matchsticks (julienne) and set aside for the remoulade. Dice the trimmings for the purée

Heat 50g butter in large saucepan and once melted, add the celeriac trimmings and season well. Allow to cook, at a relatively high heat, until the celeriac is a dark golden and cooked through. Add the milk (you may not need it all, or maybe slightly more depending on the size of your celeriac,) and blitz until smooth, then pass through a fine sieve. Keep warm over a low heat

To finish the mushrooms, transfer to a baking tray and place under a hot grill for 10 minutes to heat through

Just before serving, make the remoulade. Mix together the ingredients for the dressing then add to the juilienned celeriac and season well

To serve, add a generous spoonful of the celeriac puree to each place and top with two mushrooms. Add a mound of the remoulade on top and finish with some thyme cress or fresh thyme leaves