Wash, pit, and chop the plums.
Place the chopped plums in a large saucepan over medium heat.
2. Cook the Jam
Add sugar and lemon juice to the plums.
Stir occasionally and cook until the fruit softens and releases its juices, about 15–20 minutes.
3. Add Chocolate and Flavoring
Remove from heat and stir in the chopped dark chocolate and vanilla extract.
Mix until the chocolate melts completely and blends with the fruit.
4. Final Cooking
Return the pan to low heat and simmer for another 5–10 minutes, stirring frequently, until the jam reaches a thick consistency.
Test the jam by placing a small spoonful on a chilled plate—if it wrinkles when pushed, it’s ready.
5. Jar and Store
Pour the hot jam into sterilized jars, leaving a small gap at the top.
Seal immediately and let cool. Store in the fridge for up to 3 weeks or process in a water bath for longer shelf life.
Serving and Storage Tips
