start with the butternut squash, cut the ends off, cut in half accross the waist, then in half lengthways, then into half-rings, finally into smallish chunks. Turn the oven onto 150°C Fan at the same time.
They then need coating with oil. I would suggest putting them all in the large pan your going to make the soup in along with the oil. If you use coconut oil, warm it first. Stir round with a wooden spoon and then pour into pyrex trays.
Put the trays into the oven and set the oven for 30 minutes when they will need turning over.
Next cut the onions in half and remove peel. Chop fairly fine, and put them in the same large pan that you used to coat the butternut squash chunks in. Add enough oil to stop them sticking. Have the gas or heat set very low and cover the pan.
Next peel the garlic, crush or blitz and add to the pan.
After that cut off any manky bits from the ginger and chop finely or blitz, and add to the pan.
When the onions are nicely cooked - no need to get them too brown - turn the heat off. Add in the curry powder and turmeric, and stir well and cook for a 5 or so minutes to bring out the flavours. Probably by now the 30 minute timer will have gone off, and the butternut chunks will need a stir to cook them evenly.
The chunks will take about an hour to fully roast, but that's a question of your personal preference. They will benefit from a second turning over half way through the final 30 minutes
Tip the cooked chunks into the main pan. and then add in the water, lentils, coconut milk, finely chopped stock cubes, sea-salt,
Bring the entire pan to the boil and set the heat so it is just bubbling very gently. Cover and allow it to cook for around 45 minutes making sure to stir fairly frequently.
Check the soup towards to the end and make sure the lentils are well cooked.
Finally blend with a stick blender - or if you don't have one, you can put it in a blender. If you did the chunks nice and small, you may want to blitz just half the soup - so you still have some texture. Other people like a fully blended soup - the choice is yours. At this point you can add some lemon and enough salt to bring the flavour out fully.
Last step portion it up. I reccommend 325g containers. This made 18 portions for me. Label up and put in the freezer.