Heat olive oil in a large non-stick saucepan over medium heat.
Add the diced onion, carrot and celery and fry until onion is soft - about 5 minutes.
Next, add the spiced, garlic, ginger and lentils and stir until combined and fragrant 1-2 minutes.
Finally add the tin of tomato and water and stir.
Bring soup to the boil, then simmer on low-medium, uncovered for 20-30 minutes or until thick. Stir occasionally making sure it doesn't stick to the bottoms. Lentils can stick to the bottom if it's stirred.
Season with salt and pepper and serve with a dollop of greek yoghurt and coriander.
Notes
Note 1 - I use red lentils for this soup. I prefer red over green but both taste good! Use a non-stick saucepan and make sure you stir occasionally to avoid sticking.