It is especially easy to make if you have a bread machine, like my well-loved Zojarushi. I haven't made it on the stove before, but all the Zo does is cook it slowly and stir it gently. If I try it on the stove one day, I'll update this post. The bread machine is so easy, though. If you have a dropper bottle for your vanilla, pinch your salt, and use a fork in the lemons, there is very little to clean up.
15 oz can blueberries
1 lb frozen or fresh blueberries (no need to thaw)
1 3/4 c sugar
1/4 cup pearl Tapioca
4 pinches salt (maybe 1/4 tsp?)
4 droppers vanilla, about 1/2 tsp
Pour canned blueberries into bread machine pan. Stir in sugar, then tapioca. "Fork" lemons, squeezing in most of the juice. This is probably about 1 1/2 lemons worth of juice if you really squeeze it all out. Add the salt, vanilla, and fresh or frozen blueberries. Stir everything well one last time, without mashing the berries, and start on the "jam" cycle. When it's done, let it cool some, then pour into jars or other containers.