Decadent Chocolate Swirl Babka

1. Prepare the Dough

In the bowl of a stand mixer, whisk together the bread flour and instant yeast. Add the whole milk, large eggs, orange zest, and vanilla extract. Attach the dough hook and mix on medium-low speed for 2 minutes, just until combined. Cover the bowl with a dish towel or plastic wrap and let the dough stand for 15 minutes to hydrate.

2. Add Sugar and Salt to Dough

After the rest period, add the granulated sugar and table salt to the dough. Mix on medium speed for about 30 seconds until incorporated.

3. Incorporate Butter

Increase the speed to medium-high and gradually add the softened butter, one piece at a time, ensuring each piece is fully mixed in before adding the next. Continue kneading for 7 to 10 minutes, until the dough pulls away from the sides of the bowl and becomes smooth and elastic.

4. First Rise

Transfer the dough to a greased large bowl, turning it to coat all sides. Cover tightly with plastic wrap and let it rise at room temperature for 1 hour. Then, place the bowl in the refrigerator for at least 2 hours or up to 24 hours to allow the flavors to develop and the dough to firm up.

5. Prepare Chocolate Filling

In a medium bowl, combine the chopped bittersweet chocolate and butter. Microwave on 50% power for about 2 minutes, stirring every 30 seconds, until fully melted and smooth. Stir in the sifted confectioners' sugar, unsweetened cocoa powder, and table salt until well combined.

6. Shape the Babka

Preheat your oven to 325 degrees Fahrenheit and grease an 8½ by 4½-inch loaf pan with 1 tablespoon of butter. On a floured counter, roll out the chilled dough into an 18 by 12-inch rectangle using a floured rolling pin. Spread the chocolate filling evenly over the dough using an offset spatula, leaving a small border around the edges. Starting from one of the short ends, roll the dough into a tight log, pinching the seam to seal.

7. Cut and Twist the Dough

Using a greased serrated knife, cut the log in half lengthwise to expose the layers of chocolate. Twist the two halves together, pinching the ends to seal, and carefully transfer the twisted dough into the prepared loaf pan. Give the pan a gentle tap on the counter to settle the dough.

8. Bake the Babka

Place a wire rack in a rimmed baking sheet and center the loaf pan on the rack. Bake for 30 minutes, then cover the babka with foil to prevent over-browning. Continue to bake until the center registers 200 to 205 degrees Fahrenheit, which should take an additional 50 minutes to 1 hour.

9. Prepare Syrup

While the babka bakes, prepare the syrup by combining the granulated sugar and water in a small saucepan. Heat over medium heat until the sugar dissolves, then set aside.

10. Brush Syrup Over Babka

Once the babka is done baking, remove it from the oven and immediately brush the syrup over the top, ensuring it seeps into the crevices. Allow the babka to cool in the pan for 1 hour before transferring it to a wire rack to cool completely, which will take about 2 more hours.

11. Serve

When fully cooled, slice the babka into 1-inch thick slices and serve. Enjoy the rich, chocolatey swirls in every bite!