Heat the oven to 200C
Cut the butternut squash in half and scoop out the seeds. Brush the cut edge of the squash with oil and place cut side down on a roasting tin.
Roast in the oven for about 30 minutes or until the squash is soft all the way through.
While the squash is roasting, peel the skin off the chorizo and cut into small dice (1-2 cm)
Heat a frying pan to medium and put the chorizo into the pan, the red paprika oil will start to come out of the chorizo, you want the chorizo pieces to be slightly crispy round the edges, keep them moving so they don't burn. Once cooked take off the heat.
Cook the pasta according to the packet instructions.
Once the squash has cooked remove it from the oven and scoop out the soft flesh straight into your blender (I used my ThermoCook) or food processor.
Add the milk, cheese and butter and process until all the ingredients are blended and you have a thick sauce, if too thick add a little more milk.
Drain the pasta and mix with the chorizo, including the oils, and butternut squash sauce. Taste and season as required.
You can serve immediately or put into an ovenproof dish, cover with grated cheese and either bake immediately (200C) for 15 minutes. Or you can leave it till later and reheat from cold at 160C for 30-40 minutes.