Put chopped potatoes and carrots into a pan of hot water on a medium heat and cook for 15 to 20 minutes.
While potatoes are cooking, grill chicken for 5 to 7 minutes either side. Place on a plate and leave to cool.
Drain off potatoes and carrots and place in a slow cooker pot. Using a hand blender, puree the potatoes while slowly adding the chicken stock. Once there are no lumps, add tomato puree and stir using a wooden spoon. Place lid on slow cooker and leave on a low heat setting for 1 hour.
Dissolve vegetable stock cube in a little boiled water and add to soup along with spring onion and dried herbs. Add paprika, salt and pepper and leave for 10 minutes.
Chop up chicken fillets into small cubes and add to soup. Turn up to a medium heat, replace lid and leave for a further 20 minutes before serving with crusty bread.