1) Place the olive oil into a large 6 litre Dutch oven and set over medium heat. Once hot, add the onion, carrot, celery and salt and sweat until the onions are translucent, approximately six to seven minutes. Add the lentils, tomatoes, broth, coriander, cumin and grains of paradise and stir to combine. Increase the heat to high and bring just to a boil. Reduce the heat to low, cover and cook at a low simmer until the lentils are tender, approximately 35 to 40 minutes. Using a stick blender, puree to your preferred consistency. Serve immediately.