Peel and grate the carrots. Put them in a saucepan. Clean and chop the onion. Put it in the saucepan and boil in a small quantity of water. When the carrots and the onion boil, blend them well. Melt butter in a clean saucepan, add 5 cups of water, parsley, salt, pepper and the blended mash of carrots. Simmer soup for half an hour. Optionally add sugar and a cube of chicken stock for extra taste.