Heat the oil, braise the finely chopped onions and coarsely grated carrot in it. After 3-4 min., add the flour, stir and add the finely chopped tomatoes. Pour in 6 1/5 cups (1.5 L) water, salt and black pepper.
Once the water comes to a boil, add in the spinach (mine was frozen), then the rice. Leave on low heat to cook until the rice is ready.
In a bowl, beat the egg yolk with the yoghurt. Let the soup cool a bit, then thicken it with the yolk/yoghurt mixture.
It takes best with fresh garlic.