Chop the butternut into medium sized cubes and place in the oven with rosmary and olive oil. Roast for 20 minutes until soft.
Meanwhile, on a low-medium flame, sauté the onions in the butter for 2-3 minutes and then add the risotto rice and cook for a further 2 minutes.
Add the vegetable stock, one ladleful at a time, stirring regularly until the rice is cooked to your preferred softness. If you run out of stock, continue to add boiled water. This should take 15-20 minutes.
Once cooked, remove from the stove.
Remove the butternut from the oven, mash with a fork and add into the risotto.
Stir in the crème fraiche and add salt and pepper to taste.
Serve hot to your tot.
Recipe by Hungry Little Veggie at http://www.hungrylittleveggie.com/roasted-butternut-squash-risotto/