Pre-heat the oven to 180C.

In a mug, pour boiling water over your cashews until they are just covered.

First, you're going to get those onions caramelizing. Over the lowest possible heat, pour some olive oil into a pan and add the onions. Cook, covered, for 45 minutes to an hour. Open the lid regularly to give them a stir. If they start sticking to the pan, pour in just a little white wine or water to deglaze.

Once you've got the onions going, prepare the squash. Slice in half, lengthways, and scoop out the seeds. Place on a baking tray facing upwards. Brush a little olive oil on top. Place in the oven for about 45 minutes, until the squash is cooked through and a little browned on top. It should be ready around the same time as the onions.

Once the onions are caramelized, add the garlic and cook for about 2 minutes, until fragrant.

Now turn up the heat and add the wine until it starts to bubble. Stir it around, and it will also help to un-stick any bits of onion which stuck to the pan. It will pick up all the browned bits around the pan which will help your cleaning efforts later!

Once the wine is starting to bubble, add the almond milk and soaked cashews. Scoop the butternut squash out of its skin and add to the pan too. It's going to look a little gross right now, but don't lose the faith just yet.

Now is a good time to start your pasta going. Add to boiling water and simmer for 10-12 minutes, according to your package instructions.

Remove the sauce from the heat and puree with a hand blender, or transfer to a high speed blender, until completely smooth.

Re-heat the sauce in the pan and, finally, stir in the truffle oil after removing from the heat.

Once the pasta is cooked to your liking, drain and add to the sauce.

Top with chopped sage leaves and serve.