Peel the carrots and cut into 1/2-inch cubes. Bring a large pot of water to a boil and add the carrots. Boil gently for about 15 minutes or until the carrots are tender enough to purée. Drain and leave to cool for a few minutes.
While the carrots are boiling, whisk together the eggs, heavy cream, crème fraiche, cumin, salt and pepper in a large bowl. Set aside.
Purée the boiled carrots in a food processor. Blitz until the carrots have a smooth consistency. Add the carrot purée to the egg mixture and stir until evenly combined.
Divide the mixture between four individual size ramekins. Top each ramekin with a sprinkle of cumin seeds. Cover each ramekin with plastic wrap.
Heat the water on a double boiler or steamer. Add the covered ramekins to the steamer, cover with the lid and leave to steam for approximately 25 minutes, or until you see the flan has set in the middle. The color should be uniform and the flan should not jiggle in the middle. Carefully transfer from the steamer to your serving plates, being careful when you remove the plastic wrap. Enjoy while warm.