Mushroom and Spinach Wellington

Finely chop the cremini mushrooms by hand or in a food processor in short pulses, avoiding pureeing. Finely dice the onion, mince the garlic, strip the thyme, and chop the parsley. Drain and chop the rehydrated porcini. Beat the eggs in a small bowl and set aside.

Heat the butter and olive oil together in a large wide skillet over medium-high heat until the butter foams. Add the onion and cook, stirring occasionally, for 6–7 minutes until softened and translucent.

Add the garlic and thyme to the pan and cook, stirring constantly, for 1 minute until fragrant.

Add all the cremini mushrooms to the pan and cook over high heat, stirring every 2–3 minutes, for 12–15 minutes until all released moisture has fully evaporated and the mushrooms are dark, dry, and beginning to stick slightly to the pan.

Add the chopped porcini and white wine, then cook for 3–4 minutes, stirring frequently, until the wine is fully absorbed.

Stir in the soy sauce and 1 tsp Dijon mustard, season with salt and pepper, then remove from the heat.

Add the baby spinach directly to the hot mushroom mixture and fold through for 1–2 minutes until wilted and all excess liquid has been absorbed into the mixture.

Transfer the duxelles to a bowl and allow to cool completely at room temperature, then fold in the crumbled goat's cheese and parsley.

Cover the bowl and refrigerate for at least 1 hour until thoroughly chilled and firm.

Preheat the oven to 220°C, or 200°C for a fan oven, or gas mark 7. Unroll one sheet of puff pastry onto a lined baking sheet. Spoon the chilled mushroom filling lengthways down the centre of the pastry, shaping it into a compact log approximately 8 cm wide and leaving a 4 cm border on each long side and 3 cm at each end.

Brush the exposed border of pastry with egg wash, then brush the surface of the filling log generously with the remaining 1 tbsp Dijon mustard.

Drape the second sheet of puff pastry over the top, pressing firmly around the filling to eliminate air pockets. Trim the edges to a neat border of about 2 cm, then crimp firmly with a fork to seal.

Brush the entire surface with egg wash, score a light crosshatch pattern on top with a sharp knife (do not cut through the pastry), and sprinkle with flaky sea salt.

Bake on the middle shelf of the preheated oven for 25–30 minutes until the pastry is deep golden brown and fully puffed, and an instant-read thermometer inserted into the centre of the filling reads at least 75°C.

Remove from the oven and rest for 5 minutes before slicing with a serrated knife and serving.