Pre-heat your oven to 180c.
Cut off the top of the squash, then slice in half lengthwise. Scoop out the seeds and score the flesh.
Pop on a baking tray and drizzle with olive oil.
Roast for 45 -50 mins or until tender.
Remove from the oven and allow to cool before scooping out the inner flesh. But make sure you leave a layer around the outside.
Add the flesh to a bowl.
Meanwhile, add the onion and olive oil to a pan and fry gently for 8-10 minutes until nicely soft and caramelised.
Now add the garlic and fennel and cook for 5-6 minutes until soft.
Now add the remaining ingredients plus the squash flesh and stir to combine.
Dry toast the hazelnuts in a small pan, crush a little, then add half in.
Cook for a further minute, then turn off the heat.