2 cups blueberries fresh or frozen
1/2 cup water
1/2 cup granulated sugar
2 Tb lemon juice
2 Tb cornstarch mixed with 2Tb cold water
Combine blueberries, water, sugar and lemon juice in a medium saucepan. Bring to a low boil over medium heat. Cook for 2 minutes, stirring occasionally being careful not to break the blueberries. Slowly add cornstarch slurry while stirring blueberries. Bring back to a boil and cook until thickened (30 - 60 seconds). Cool completely before using. If too thick, add some water to thin out.