I have no idea what the variety of plum is that some generous neighbors dropped at the front door last week. The skin is a smooth, deep, dark crimson and the flesh is mostly the same color, although it becomes orange toward the stone in the less ripe fruit. The plums are large, the size of a small nectarine.
I let them sit a week off the tree, ate a few, and made jam from the rest.
Bring to a boil, then simmer for 15 minutes or until plums are soft:
740 g chopped and pitted Tuuri plums
250 ml water
Juice and pulp of one small Eureka lemon
Meanwhile, wash and sterilize four 8 oz jars and warm 740 g raw organic sugar in a 250 degree F oven. Once the jars are sterilized, dry them and keep them warm by keeping them in the oven too.
When the plums are soft and the mixture had reduced by around a third, add the warm sugar and stir until sugar is completely dissolved. Bring to a boil then adjust heat so jam is bubbling but won’t bubble over. Cook 15 minutes, stirring toward the end to ensure jam doesn’t stick to the bottom or sides of the pan. Test set on a cold plate before finally removing jam from the heat.
Pour jam into hot jars and can 10 minutes.