Peel & chop the onions, garlic and carrots.
Heat the oil over a medium heat and sauté the onions & garlic until softened - about 2 minutes - then stir in the spices and cook for another 5 minutes.
Add the carrots and cook for another 10 minutes, stirring occasionally, until softened.
In the meantime, wash the lentils until the water is clear, then add to the pan together with the tomatoes and stock. Season to taste.
Bring to the boil, put on the lid, cook under pressure for 7 or 8 minutes then allow to cool.
Serve in bowls with the garnish - squeezing in the lemon juice.