Peel and trim the onion, and trim the celery, carrots and courgette. Scrub the sweet potato clean, then chop it in half along with the squash (there’s no need to peel it).
Place all the veg on a roasting tray and drizzle with extra virgin olive oil. Roast for around 1 hour, or until all the veg is soft, then tip into a large jug.
Add a good splash of boiling water, then blitz with a stick blender to your desired consistency. At this stage, remove a portion for your baby, if needed (you can freeze in ice-cube trays for another day).
Place the remaining blitzed veg into a pan add the stock, then season with sea salt and black pepper. Add the pastina or break in the spaghetti/linguine, then stir through the soup, adding a splash more water to loosen if the soup is quite thick because the pasta will absorb the water.
Place on the hob for 10 to 12 minutes, or until the pasta is cooked through.
Serve with good grating of Parmesan cheese (not for your baby, and only a little for toddlers).