Vegetables: Peel and dice 1/4 pumpkin into small pieces. Dice 1 onion and 1/2 leek. Set aside.
Sausage: Remove the casing from 2 sausages. Heat a large pan to medium heat and add the sausage meat. Break up the sausage into small bits, cooking for 4-5 minutes until crispy. Remove from the pan, and add the vegetables and 1 tsp crushed garlic. Add 1/4 cup vegetable stock to the pan, scrape up any bits of sausage and let the vegetables cook for 5-10 minutes to soften.
Pasta: Bring a large pot of water to a boil and cook pasta as per packet instructions.
Sauce: Take the vegetables off the heat, and using either a blender or stick blender, blitz the vegetables into a sauce. If the sauce is too thick, add 1 tbs water at a time until it can blend nicely. Season with 1/2 tsp salt, 1 tsp pepper, 1 tsp mixed herbs. Taste and adjust seasoning if required.
Assemble: Drain the pasta water, keeping 1/2 cup to use if needed, add the pumpkin sauce to the pasta and mix carefully. Add a splash of reserved pasta water and add the sausage bits. Mix everything together, adding a little bit of pasta water if needed.
Serv: Plate up and serve with grated parmesan cheese on top.