Roughly chop the onions. Cut the carrots into thin slices. Steam both in the butter for about 5 minutes. Add the stock and simmer for approx. 15 minutes. Then puree everything, add orange juice and bring to the boil. Finally add the cream and season with salt and pepper.
For the gremolata, roughly chop the parsley, lemon zest, garlic, parmesan and pitted dates in a blender. Sprinkle over the soup before serving.