
These individual butternut squash Wellingtons wrap tender squash in golden puff pastry with a savory mushroom, spinach, walnut, and blue cheese filling. Finished with a thyme-scented orange gravy, they make an impressive vegetarian centerpiece for a cozy dinner or holiday meal.
Prepare the squash neck by trimming it to about 15 cm long, peeling it, and cutting it in half lengthwise. Save the rounded base for another recipe. Place the squash halves in a lidded pan with the butter, orange juice, thyme sprigs, vegetable stock, and a generous seasoning of salt and pepper. Cover, bring to a gentle simmer over medium heat, and cook for 25-30 minutes, until the squash is just tender but still holds its shape. Lift out the squash, reserve the cooking liquid, and let the squash cool completely.
On a lightly floured surface, roll the puff pastry into a large rectangle about 5 mm thick. Cut it into four equal rectangles, each large enough to enclose one squash half with room for sealing around the edges. Transfer the pastry pieces to a tray and chill while you prepare the filling.
Heat a dry frying pan over medium-high heat. Add the chopped mushrooms and cook for 6-8 minutes, stirring often, until their moisture has evaporated and they begin to brown. Add the spinach and cook for 1-2 minutes, until wilted. Stir in the thyme leaves, season to taste, then add the chopped walnuts and cook for 1 minute more, just until fragrant. Transfer the mixture to a bowl, crumble in the blue cheese, mix well, and leave to cool.
Heat the oven to 200 C conventional or 180 C fan. Place two pastry rectangles on a lined baking tray. Spoon a little of the mushroom filling onto the center of each, then set one cooled squash half on top. Press the remaining filling over and around the squash to form a compact mound. Brush the exposed pastry edges with beaten egg, cover each with a second pastry rectangle, and press or crimp the edges firmly to seal. Brush the tops with the remaining egg wash.
Bake the Wellingtons for 35-40 minutes, until the pastry is deeply golden, crisp, and cooked through. Let them rest for a few minutes before serving so the pastry stays neat when cut.
To make the sauce, stir 3 tsp of the reserved squash cooking liquid into the cornflour to form a smooth slurry. Strain the remaining cooking liquid into a small pan, bring it to a simmer, then whisk in the slurry. Cook briefly, stirring, until the sauce thickens. Spoon the warm sauce over the Wellingtons to serve.
Cool both the squash and mushroom filling before assembling so the puff pastry stays flaky instead of turning soft. Cook the mushrooms until their liquid has evaporated to prevent a soggy filling. For a milder flavor, replace the blue cheese with goat cheese or a sharp vegetarian cheddar. The filling and cooked squash can be prepared a day ahead and chilled separately before assembly.