1. 1. Prepare Your Baking Surface and Oven: Preheat your oven to 375 F (190 C). Line a baking sheet with parchment paper to prevent sticking and make cleanup a breeze. This step ensures your babka bakes evenly and releases easily.

2. 2. Unroll and Spread the Dough: Open the can of crescent rolls and carefully unroll the dough onto your prepared baking sheet. Gently press the seams together to form one large rectangle. If there are perforations, pinch them firmly to create a solid sheet of dough. Brush the melted butter evenly over the entire surface of the dough, leaving a small border around the edges.

3. 3. Create the Blueberry Lemon Filling: In a small bowl, combine the fresh blueberries, granulated sugar, lemon zest, lemon juice, and optional cinnamon. Gently toss everything together until the blueberries are well coated. This mixture will be spread over your dough, providing that burst of flavor.

4. 4. Spread the Filling and Roll the Dough: Evenly spoon the blueberry mixture over the buttered dough, making sure to distribute the berries as much as possible. Starting from one of the longer sides, carefully roll the dough into a tight log. Take your time with this step to keep the filling secure inside.

5. 5. Shape the Babka Braid: Using a sharp knife, carefully slice the log lengthwise down the middle, exposing the beautiful swirled filling. Turn the cut sides up. Gently twist the two halves together, keeping the cut sides facing outwards as much as possible. Once twisted, carefully form the twisted log into a circle or an oval shape, pinching the ends together to seal.

6. 6. Bake Until Golden Brown: Transfer the shaped babka (still on the parchment paper) to the preheated oven. Bake for 20-25 minutes, or until the babka is golden brown and the filling is bubbly. The color is your best indicator of doneness.

7. 7. Prepare the Lemon Glaze: While the babka bakes or cools slightly, whisk together the powdered sugar with 1-2 teaspoons of milk or water in a small bowl until you achieve a smooth, pourable glaze. Add more liquid a tiny bit at a time if it’s too thick, or more powdered sugar if it’s too thin.

8. 8. Cool and Glaze: Let the babka cool on the baking sheet for about 10-15 minutes before drizzling generously with the lemon glaze. This cooling period helps the babka set and prevents the glaze from melting completely into the bread. Slice and serve warm or at room temperature.