Make the mushroom duxelles. Heat olive oil in a large skillet over medium-high heat. Add the very finely diced shallots and cook for 3 minutes until soft. Add the minced garlic and cook for 1 minute. Add the finely diced mushrooms. Cook the mushrooms for 12–15 minutes, stirring occasionally, until every single drop of moisture has completely evaporated and the mushrooms have reduced to a deeply golden, intensely flavored, almost paste-like consistency. Add soy sauce, balsamic vinegar, thyme, rosemary, smoked paprika, salt, and pepper. Cook for 2 more minutes. Remove from heat and allow to cool completely.

Make the lentil and walnut filling. In a large bowl combine the drained lentils, toasted walnuts, soy sauce, smoked paprika, garlic powder, cumin, salt, and pepper. Mash roughly with a fork — aim for a chunky mixture with plenty of texture remaining. Set aside.

Make the cashew cheese. Blend the soaked cashews, nutritional yeast, lemon juice, garlic, Italian herbs, salt, pepper, and water in a high-speed blender until completely smooth and creamy. Adjust water to achieve a thick, spreadable cream cheese consistency. Set aside.

Cook the spinach. Heat olive oil in a small pan over medium heat. Add garlic and cook for 30 seconds. Add the spinach and cook for 1–2 minutes until completely wilted. Squeeze out all excess liquid using the back of a spoon or a clean towel. Season with salt and pepper. Allow to cool.

Prepare your work surface. Lay a large sheet of parchment paper on a clean, flat surface. Unroll one sheet of vegan puff pastry onto the parchment. If necessary roll it gently with a rolling pin to a rectangle approximately 30x25cm.

Build the layers. Working carefully and leaving a 4cm border on all sides, build the filling layers in the following order from bottom to top: Spread the cashew cheese in an even layer over the center of the pastry leaving the border clear. Arrange the cooled wilted spinach evenly over the cashew cheese layer. Spread the cooled mushroom duxelles evenly over the spinach in a compact, uniform layer. Press the lentil walnut mixture firmly and evenly over the mushroom duxelles.

Roll the Wellington. Brush the border of pastry around the filling generously with plant-based milk. Lift the parchment paper to help roll the pastry tightly around the filling from the long side. Pinch the seams and ends firmly to seal completely.

Transfer to baking tray. Carefully transfer the rolled Wellington seam-side down onto a large parchment-lined baking tray. Refrigerate for 20–30 minutes.

Preheat your oven to 200°C (400°F). Remove the Wellington from the fridge. Mix the plant-based milk and maple syrup together in a small bowl. Brush the entire surface of the Wellington generously with this glaze. Score a decorative diagonal pattern across the top of the pastry.

Bake the Wellington. Place the prepared Wellington in the center of the preheated oven. Bake for 35–40 minutes until the pastry is deeply golden all over.

Allow the Wellington to rest on the baking tray for 10–15 minutes before slicing.

Make the red wine gravy. While the Wellington bakes heat olive oil in a medium saucepan over medium heat. Cook the shallots for 5 minutes until golden. Add garlic and cook for 1 minute. Add tomato paste and cook for 1 minute. Pour in the red wine and simmer vigorously for 3 minutes until reduced by half. Add vegetable stock, soy sauce, thyme, balsamic vinegar, and maple syrup. Simmer for 10 minutes. Add the cornstarch mixture and stir for 2 minutes until the gravy has thickened beautifully.

Transfer the rested Wellington to a large serving board. Using a sharp serrated knife cut into generous slices. Serve immediately with the warm red wine gravy.