- 8 oz. fresh or frozen blueberries
- 3 ⁄4 cup sugar
- 1 ⁄2 teaspoon lemon juice
Combine the blueberries, sugar, lemon juice, and 1⁄4 cup water in a 2-qt. saucepan over medium-high heat.
Cook, stirring occasionally, until thickened, 8–10 minutes. Remove pan from heat and mash the blueberries with a wooden spoon until chunky; let cool.
Spoon about 1 tbsp. filling into each kolache before baking.