Finely dice all your vegetables and add them to the slow cooker.
Pour in the stock and give everything a good stir.
Cook on high for 4 hours.
Use a stick blender to blend the soup to your desired consistency.
Stir in some single cream (optional)
Notes
Cut all the vegetables evenly, in to small pieces so that they will cook quickly. Big chunky bits of vegetables will take much longer to cook, especially the root vegetables.
You don't have to peel the carrots and potatoes. It will save time and add fibre.
Spice this soup up a little with a sprinkling of red chilli flakes before serving or even adding some curry powder at the same time as the vegetables.
If you are making this soup for young children, then use a low salt stock.
If blending this in a jug blender, allow to mostly cool first, so the heat doesn't crack the blender.
You can make this more of a filling soup by stirring in a can of chickpeas.
A little bit of grated cheddar, crumbled stilton or Parmesan shavings on top finishes this perfectly.