RINSE the lentils well and put them in a large saucepan with the vegetable stock and bring to a boil. Reduce the heat, add the carrot, celery & half the ginger, cover and simmer for about 20- 30 minutes, until the lentils are cooked.
TOAST SPICES - in a small dry frying pan dry toast the curry powder & spices over a low heat until fragrant, and don’t let it burn. Tip this into a small bowl and set aside.
COOK - In the same pan heat the butter, ghee or oil over a medium heat, add spring onions, the rest of the ginger, garlic, chilli, vinegar and raisins. Cook for 2 minutes stirring constantly.
ADD - the tomato puree and cook for another minute. Add the toasted spices to the tomato mixture along with the thyme and oregano. Mix well and add this to the simmering lentils along with the coconut milk, seasoning generously with salt and black pepper.
SIMMER uncovered for ~20 minutes, then remove from heat, and puree with a hand held blender until smooth. Add more broth slowly, if needed to reach desired consistency, to be more or less soupy according to your preference.
ADD in mandarin juice and check for seasoning.
SERVE in warmed bowls topped with a swirl of Greek yogurt, sour cream or creme fraiche