Sand plum jelly
Sand plum jelly is made by cooking the fruit until it is soft and then straining the juice. The juice is then boiled with sugar until it thickens into a jelly. Sand plum jelly is a popular spread for toast, biscuits, and pancakes. It can also be used to make pies, jams, and other desserts.
Instructions
In a large pot, combine the sand plums and water. Bring to a boil, then reduce heat and simmer until the plums are soft, about 30 minutes.
Strain the juice from the plums, discarding the pulp.
In a large saucepan, combine the juice and sugar. Bring to a boil, then reduce heat and simmer until the jelly reaches 220ºF on a candy thermometer, about 20 minutes.
Stir in the pectin and cook for 1 minute more.
Pour the jelly into hot, sterilized jars and seal. Let the jars cool on a wire rack. Store the jelly in a cool, dark place.
Notes
Sand plums are small, round fruits that grow on wild plum trees in North America. They are typically yellow or orange in color and have a tart, sour flavor. Sans plums are also known as the wild plums, prairie plums, or sand cherries.
Source
Food in the U.S.A.