If using a soup kettle then soak your lentils for at least half an hour. This step is optional if you plan to cook the soup on the hob.
Add all the vegetables to a soup kettle or large pan. Add the tinned tomatoes then use the tin to add 2 tin’s worth of water. Add the rest of the ingredients.
If using a soup kettle set to purée programme and start.
If using a saucepan, bring everything to the boil then turn down the heat and simmer until everything is cooked through. Blend using a hand blender or liquidiser.
If the soup is too thick add water to desired consistency. Taste and adjust seasoning if necessary.