Peel the carrots and blitz in a mini chopper/food processor and add to the lentils.
Fill the slow cooker with water and cook on high for approx 6 hours until the lentils are very mushy.
Transfer to a large pot and make as thick or thin as you want by adding more water now add the Swiss vegetable bullion and simmer for a further hour. Fantastic cheap and simple you can also freeze if it lasts long enough.
Marigold Swiss® vegetable bouillon is available in a tub from all supermarkets.