Heat a heavy stock pan over medium heat. Add the olive oil and the vegetables. Sauté for 4-5 minutes until they just begin to soften.
Next add the spices. Stir them in and mix well with the vegetables - add the lentils and sauté for another minute and add the stock & water.
Increase the heat to high and bring to a boil, reduce to medium low and continue to simmer the soup, stirring occasionally. It will take about another 15 minutes until the lentils are completely cooked.
When the lentils are cooked, remove from the heat and finish by squeezing the juice of half a lemon into the soup, stir to combine and serve.