Bring 4 ¾ cups water and 3 ⅓ cups sugar to a boil.
Add one (1 lb.) package of blueberries and bring to a boil again.
Thicken with three rounding ⅓ cups of Red Berry Pie Tone diluted with 1 cup water OR three rounding ⅓ cups corn starch.
Remove from the stove.
Fold in two more (1 lb.) packages of blueberries and let cool.