Soften the onions in sunflower oil in a heavy, covered pan. Add the butter and the carrots and continue softening for 10 to 15 minutes (the onions does not brown !); then add the apples. Soften for another 5 to 10 minutes, stirring occasionally, until the apples have begun to disintegrate. Cover with the water, bring to a boil and simmer for 20 to 30 minutes. Allow to cool slightly, then liquidize, adding the salt, black pepper and marjoram before you do so.
From: Brigid Allen, The soup book, M Papermac 1993