1. Heat the oil and butter in a large saucepan until the butter is melted. Add the onions and toss to coat. Sprinkle on the brown sugar. Cover the pan and cook over low heat until the onions are golden. 2. Pour in the chicken broth. Add the parsnips and potatoes. Cover the pan and simmer for 30 minutes or until tender. Meanwhile, grate the apples and place them in a bowl. Sprinkle on the lemon juice and toss to coat. Set aside. 3. Pour the parsnip mixture into the container of a blender or processor and whirl until smooth. Return to the saucepan. Stir in the apples, cinnamon, mace, and brandy. Cook for 20 minutes or until the apples release their flavor. Remove from the heat and gradually blend in the cream. Season with salt and pepper. Return to low heat and warm gently. Do not allow the soup to boil. Ladle into soup bowls and garnish with a dusting of freshly grated nutmeg.