Sort the fruit, remove the stem and wash thoroughly. Slowly bring to the boil with water and preserving sugar and continue to simmer for at least 4 minutes, stirring occasionally. Stir in the citric acid and immediately pour the hot jam into sterilized, clean jars and close tightly with a twist-off lid. Turn it upside down for 10 minutes, then turn it over and let it cool.
As a spread or for dessert, e.g. vanilla ice cream.