With 25 lbs of blueberries in the fridge, we just had to try this out ... it was SO easy. No cooking even.
This jar is for the fridge. I have two larger plastic ones in the freezer. Yum.
I found this one on Canadian Living ...
3 C. blueberries, crushed
1 T. lemon juice
2 T. sugar
1 box (49 g) light pectin crystals
In large bowl, stir blueberries with lemon juice. Add sugar. Mix in pectin crystals; let stand for 30 minutes, stirring occasionally. Pour into clean airtight containers, leaving 1/4-inch (5 mm) headspace. Let stand, undisturbed, until set, 24 hours. Store in refrigerator for up to 3 weeks or freeze for up to 8 months.