Prepare the Dough: In a large mixing bowl, combine the all-purpose flour, salt, sugar, and yeast. Gradually mix in the lukewarm water until you form a smooth and elastic dough. Cover with a cloth and let it rise for about 1 hour, or until it has doubled in size.

Roll Out the Dough: Once the dough has risen, punch it down gently. Divide it into smaller portions for easier handling. On a floured surface, roll each piece into a thin circle, about 1/8 inch thick.

Fill the Pierogi: Place 3-4 fresh blueberries in the center of each circle. Sprinkle a tiny bit of sugar over the blueberries to enhance their sweetness. Carefully fold the dough over to encase the berries and pinch the edges tightly to seal.

Steam the Pierogi: Bring water to a boil in a steamer or pot with a steaming basket. Carefully place the sealed pierogi in the steamer, ensuring they aren’t touching each other. Steam for about 7 minutes, or until they are light and fluffy.

Serve and Enjoy: Once steamed, transfer the pierogi onto a serving plate. They’re best enjoyed warm, either plain or topped with a dollop of sour cream or a light dusting of powdered sugar.