Heat the oven to 200°C/400°F. Put the butternut squash on a baking sheet, drizzle with olive oil and season with salt and pepper. Roast for 40 minutes. Once roasted blend until smooth and set aside.
Cook the pasta according to packet instructions. Reserve 100-200ml of pasta water. Cut open the sausages and remove the skins. Heat 2 tablespoons of olive oil over medium heat and add the sausage meat. Break the meat up with a wooden spoon into chunks. Add the cayenne pepper and smoked paprika. When the sausage meat has browned remove from the pan with a slotted spoon.
Turn the heat down to medium low and add the butter. Once melted add the thyme sprigs and cook gently until the butter has turned a pale brown then remove the thyme. Add the squash, sour cream and pasta water (start with half and add more if you need to thin it out more) then season well. Add the cooked pasta and toss the sauce through the pasta with tongs. Return the sausage to the pan and toss again. Serve.
Nutrition information is an estimate and will vary depending on the exact ingredients used.