Peel and roughly chop the carrots and add them to a large saucepan.
Peel and roughly chop the onion and add it to the saucepan with the carrots.
Dice the potato (no need to peel) and add it to the saucepan with the carrots and onion.
Add the lazy garlic, tomato purée and lentils to the saucepan.
Fill the saucepan with water and bring to the boil.
Add the chicken stock or stock cubes of choice, stir well, and simmer for 30 minutes, until the carrots are tender if poked with a fork, and the lentils are mushy.
Take the saucepan off the heat and blitz with a stick blender (or blend in a food processor or blender).
Taste and season accordingly, and serve while hot.
Notes
After the leftover soup has cooled, I store it in the fridge and re-heat as needed. As the soup thickens when cool, you might want to add a splash of hot water to the soup as you re-heat it.