Ingredients

Step by step

1. Preheat the oven to 180°C, fan 160°C, gas 4. Put the porcini mushrooms for the tomato sauce into a large mug, cover with boiling water and set aside. Put the squash and aubergines in a bowl with the chilli powder, some seasoning and 3 tablespoons of olive oil and toss to coat. Lay the squash on a lined baking tray, and the aubergines on another, and roast both for 45 minutes.
2. Meanwhile, make the tomato sauce. Heat the olive oil in a large deep pan over a medium heat. Add the onion and cook for 3 minutes to soften. Stir in the garlic and cook for a further 3 minutes.
3. Pulse the carrot, celery, red pepper and rosemary leaves in a food processor until finely chopped (or chop by hand). Add to the pan and cook for 15 minutes. Pour in the red wine, increase the heat to medium-high and cook for a further 5-7 minutes until the wine has cooked off but left everything a lovely red colour. Take the porcini out of the mug and finely chop. Add to the pan with the liquid from the mug, the chopped tomatoes and the sugar. Stir and simmer for a further 10 minutes.
4. Remove the trays of vegetables from the oven. Drizzle the aubergine with the balsamic vinegar and mix well. If the butternut squash is very wet, drain it in a sieve, pressing out the liquid. Transfer to a large bowl and quickly mash.
5. Add the aubergine to the tomato sauce and simmer for a further 20 minutes, stirring occasionally, until the sauce has thickened. Taste and season. Take off the heat and set aside.
6. Meanwhile, make the bechamel. Cook the cashews in boiling water for 10 minutes. Warm the plant-based milk in the microwave. Melt the dairy-free spread in a pan over medium heat. Turn the heat right down and add the flour to the pan, stirring until you have a paste. Gradually pour in the warm milk, stirring until you have a thick, creamy sauce. Add the garlic, nutritional yeast, if using, onion granules plus a pinch of salt and pepper. Squeeze in the lemon juice, catching any pips with your other hand. Drain the cashews and rinse with cold water. Blend to a fine cream with 100ml water in a liquidiser. Pour the bechamel into the liquidiser and blend everything together.
7. Put the remaining oil in a large saucepan over a medium heat. Add the spinach, cover with a lid and cook for 5 minutes until wilted. Transfer to a sieve and squeeze out as much liquid as you can.
8. Lightly oil a 25cm x 35cm baking dish and cover with lasagne sheets, breaking them if necessary to make a complete layer that will seal in the steam and properly cook the pasta. Spoon in a third of the tomato sauce, then lay a third of the spinach on top, followed by a third of the squash. Drizzle over a quarter of the bechamel sauce. Repeat twice more with layers of pasta, then tomato sauce, spinach, squash and bechamel. Top with a final layer of pasta, using broken pieces to fill any gaps (try to avoid overlaps) and cover with the remaining bechamel. Put a few rosemary leaves on top. Cover the lasagne with foil, put in the oven on the lowest shelf and bake for 50 minutes. Remove the foil and bake for a further 15 minutes, then leave to stand for 10 minutes. Serve with a green salad and a little balsamic glaze, if you like.
   
   Recipe adapted from BOSH! by Henry Firth and Ian Theasby (HQ, £20).