Preheat the oven to 180°C / 356°F fan-assisted.
Peel the butternut squash, remove the seeds and dice the flesh into small bite-sized pieces (you can roast the seeds separately for a tasty snack). Transfer to a baking tray, drizzle with a splash of olive oil and season with salt and pepper. Roughly chop the sage leaves and add half to the butternut squash, then use your hands to mix everything together. Roast in the oven for 25 minutes or until the squash just begins to char around the edges.
Add a splash of oil to a large saucepan over a medium heat. Add the remaining chopped sage leaves and fry for 3 minutes or until crispy. Remove the sage and transfer to a plate lined with kitchen paper to soak up any excess oil.
Peel and dice the onion, then transfer to the saucepan and fry for 6 minutes or until the onion becomes translucent, but not brown. Stir occasionally and add a splash more olive oil if necessary.
Meanwhile prepare the vegetable stock in a separate saucepan, bring it to a boil, then leave it on a very low heat so it remains warm while you cook the risotto.
Peel and dice the garlic, and transfer to the saucepan with the onion. Fry for 2 minutes, stirring occasionally.
Next add the rice and fry for a minute to lightly toast, stirring occasionally.
Add the wine, give everything a good stir and leave to simmer for a couple of minutes until most of the wine has evaporated.
Start adding the vegetable stock a ladle at a time, waiting until most of the stock has been absorbed before adding another ladle. Repeat this process for 20-30 minutes, until most of the stock has been added to the risotto and there’s a slight ‘bite’ to the rice.
When the risotto is almost ready, add the nutritional yeast, juice from half the lemon and the spinach. Give everything a good stir and cook for a minute or until the spinach has wilted. The rice should be creamy and sticky, but not clumpy. If it feels too clumpy, add a splash of remaining vegetable stock.
Take the risotto off the heat, add the butternut squash and give the risotto another final stir.
Serve in bowls and top with a sprinkling of remaining fried sage leaves and a small handful of rocket.