Pop the lid on the pot, and let the vegetables “stick” a little bit: I find that this imparts a lovely flavour to the soup. Putting the lid on also steams the vegetables so that they cook a bit quicker. Keep shaking the pot with the lid on, almost as if you are making popcorn. Take the lid off from time to time, and scrape off any bits that have caramelised on the bottom. Keep doing this for about ten minutes, and then add the Marigold and litre of water. Stir well, making sure you have scraped off the bits on the bottom, and bring to a boil. Turn down to a simmer, and simmer until the vegetables are soft, which should take around 25-30 minutes.