I bought the most tart blueberries I've had in a lon g time last weekend at Costco. I could barely eat them and DH and Ava wouldn't eat them at all. It was a Costco sized package that I was afraid would go to waste.
So I made blueberry sauce, and it so freaking delicious, I could just eat it alone - lol! But instead of being a piggy, I froze it into two portions to use for pancakes or blintze souffle later.
in a pan, add 2 cups blueberries, 1/4 cup water, 1 cup orange juice, and 3/4 cup white sugar. Bring to low/slow boil, stirring gently now and then.
in the meantime, in a measuring cup, add 1/4 cup water and 3TB cornstarch - whisk/blend fully.
once lightly boiling, slowly pour in the cornstarch/water mixture and continue to gently stir until incorporated. you don't want to break up the blueberries, although some will pop.
stir occassionally for 3-4 minutes, until sauce thickens enough to coat the back of the spoon.
remove from heat. Add 1/2tsp almond extract and 1/8tsp ground cinnamon. Stor to combine.
Serve warm - Enjoy!
I've made this before - it freezes and reheats really well, and it totally salvages tart blueberries!