The soup always has a different flavour depending on which vegetables are left. Butternut squash usually appears in there, along with carrots and onions. I've also used sprouts, cabbage, parsnips as well as the odd tomato and wilting rocket.
Combined with garlic and chicken or vegetable stock I cook in the slow cooker for a few hours and then blend until smooth. It makes a great after school meal on a Friday, as well as lunch on Saturday, served with home-made bread or pitta bread.