Peel and dice the onion. Heat the oil in a non-stick pan and fry the onion in it. Peel the carrots and clean the cauliflower florets. Cut both into slices and add them together with the red lentils. Sprinkle the spices over it and pour the vegetable stock over it. Simmer for approx. 15 minutes with the lid closed. Season to taste, stir in the sour cream and sprinkle with the coriander greens.