Moravian Berry Kolache with Streusel

Make the Dough

1. 1In a large bowl, combine flour, sugar, yeast, and salt.
2. 2In a separate bowl, whisk together warm milk, melted butter, and beaten eggs.
3. 3Pour the wet ingredients into the dry ingredients and mix until a shaggy dough forms.
4. 4Turn the dough out onto a lightly floured surface and knead for 8-10 minutes until smooth and elastic.
5. 5Place the dough in a lightly greased bowl, cover, and let rise in a warm place for 1-1.5 hours, or until doubled in size.

Prepare the Filling

1. 1In a saucepan, combine mixed berries, sugar, and lemon juice. Cook over medium heat, stirring occasionally, until berries start to break down.
2. 2Stir in the cornstarch slurry and cook for another 2-3 minutes, until thickened.
3. 3Remove from heat and let cool completely.

Make the Streusel

1. 1In a medium bowl, combine flour, sugar, and cinnamon (if using).
2. 2Cut in the cold butter using a pastry blender or your fingertips until the mixture resembles coarse crumbs.
3. 3Set aside.

Assemble and Bake

1. 1Preheat oven to 375°F (190°C). Line baking sheets with parchment paper.
2. 2Punch down the risen dough and divide it into 12 equal portions. Roll each portion into a ball.
3. 3Place the dough balls on the prepared baking sheets, leaving space between them.
4. 4Using your thumb or the back of a spoon, create an indentation in the center of each dough ball, forming a well.
5. 5Spoon a generous amount of the cooled berry filling into each well.
6. 6Sprinkle the streusel topping evenly over the filling and around the edges of the dough.
7. 7Bake for 18-20 minutes, or until the kolaches are golden brown and the topping is crisp.
8. 8Let cool on the baking sheets for a few minutes before transferring to a wire rack to cool completely.