Yields two pints of syrup
(2) 10 oz bags frozen blueberries
1/3 c. white sugar
2 1/2 c. water
1/3 c. cornstarch
In a saucepan, combine blueberries, sugar and 2 c. of water. Bring to a low rapid boil; maintain for 10 minutes, stirring occasionally. Whisk cornstarch together with 1/2 c. cold water. Pour cornstarch mixture into syrup. Return to low boil; maintain for 2-5 minutes or until syrup thickens. Cool partially.
Pour syrup into jars or plastic containers. If using pint jars, you can seal them and follow regular canning procedures. Otherwise, refrigerate or freeze the syrup until you're ready to use it.