Ingredients:
- 4 cups blackberries (fresh or frozen, 600g)
- 2 cups granulated sugar (400g)
- 1/4 cup lemon juice (60ml)
- 1 teaspoon vanilla extract (5ml)
- 1 teaspoon cinnamon (optional, for added warmth)
- Sterilized jars and lids
- Water bath canner or large pot
Instructions:
- Wash blackberries thoroughly, removing any stems.
- In a large saucepan, combine blackberries, sugar, lemon juice, and spices (if using).
- Place over medium heat, stirring until sugar dissolves.
- Increase heat and bring to a rolling boil, stirring frequently.
- Cook until the mixture thickens, about 20-30 minutes, testing by placing a spoonful on a cold plate; it should set after cooling.
- Carefully transfer the jam into sterilized jars using a funnel, leaving 1/4 inch headspace at the top of each jar.
- Wipe rims to ensure a good seal, place lids on, and process in a water bath for 10 minutes if canning.
- Remove jars from water bath, let cool, and store in a cool, dark place.