Ingredients:
- 4 cups (500g) fresh blackberries, washed and hulled
- 3 cups (600g) granulated sugar
- 1/4 cup (60ml) lemon juice, freshly squeezed
Instructions:
- Sterilize jars and lids. Keep them warm until ready to fill. (Boil or run through a dishwasher cycle).
- In the heavy-bottomed pot, combine blackberries, sugar, and lemon juice.
- Cook over medium heat, stirring frequently, until the sugar dissolves.
- Increase heat to medium-high and bring the mixture to a rolling boil that cannot be stirred down.
- Use a candy thermometer to reach 220°F (104°C) OR place a small spoonful of jam onto a chilled plate. Let it cool for a minute, then push it with your finger. If it wrinkles, it's ready.
- Once the jam reaches the setting point, remove from heat and skim off any foam from the surface.
- Carefully ladle the hot jam into the sterilized jars, leaving about 1/4 inch (6mm) headspace.
- Water bath process jars for 10 minutes for longer shelf life. Alternatively, invert jars for 5 minutes, then turn upright. OR Simply let them cool completely, checking for proper sealing (lid should be concave).
- Let jars cool completely before storing in a cool, dark place.