Quarter the carrots and peppers and mix in a bowl with two tablespoons of olive oil (possibly more). Heat in the very hot oven for 10 minutes, grill over if possible, until the peppers are slightly dark.
In the meantime, chop the onion and sweat in the remaining olive oil. Add the carrots and paprika, season with cinnamon, pepper and salt. Add the vegetable stock and the juice of the lime and bring to the boil.
Then reduce the heat and simmer for 20 minutes (or until the carrots are tender). Puree the soup and serve garnished with creme fraîche.