You can make plum jam with just the basics — plums, lemon juice, water, and sugar — but the cinnamon and almond extract in this recipe make for a subtly complex spread.

Steps

1. Combine all the ingredients in a large pot. Stirring frequently, bring the jam to a boil, then lower the heat to a simmer. Cook, stirring frequently, until the jam is dark and thick, about 1 hour.
2. Meanwhile, bring a large pot of water to a boil. Sterilize 5 to 6 half-pint canning jars in the boiling water for 10 minutes; soak the jar lids and ring bands in hot water. Fill each jar with hot jam, wipe the rims clean, place the lids on the jars, and screw on the ring bands. Submerge the filled jars in the pot of water, turned down to a gentle boil, for 10 minutes. Transfer the jars to a dishtowel and place at least 1 inch apart; let cool for 24 hours.