1. Make the Dough

1. In a small bowl, combine warm milk, yeast, and 1 tsp sugar. Let sit 5–10 minutes until frothy.

2. In a large bowl (or stand mixer with dough hook), combine flour, remaining sugar, salt, and lemon zest.

3. Add yeast mixture, eggs, and vanilla. Mix until a rough dough forms.

4. Add butter, one cube at a time, kneading after each addition. Continue kneading 10–12 minutes until the dough is smooth and elastic (it should pull away from the bowl sides).

5. Place in a lightly oiled bowl, cover, and let rise 1½–2 hours, or until doubled in size.

2. Make the Blueberry Filling

1. In a small saucepan, combine blueberries, sugar, and lemon juice.

2. Cook over medium heat for 5–7 minutes, stirring, until berries burst and mixture thickens slightly.

3. Stir in cornstarch slurry; cook another 1–2 minutes until thick and jammy.

4. Remove from heat and let cool completely.

3. Make the Cream Cheese Filling

In a small bowl, beat together cream cheese, sugar, lemon zest, lemon juice, and vanilla until smooth.

4. Assemble the Babka

1. Punch down risen dough and roll into a large rectangle (~10×14 inches).

2. Spread cream cheese filling evenly over the dough, leaving a ½-inch border.

3. Spoon the cooled blueberry filling over the cream cheese and gently spread.

4. Roll tightly from the long side into a log.

5. Use a sharp knife to cut the log in half lengthwise. Twist the two halves together, keeping the cut sides facing up to show the layers.

6. Transfer carefully into a greased 9×5-inch loaf pan.

5. Second Rise

Cover loosely and let rise 45–60 minutes, until puffy and almost doubled.

6. Bake

• Preheat oven to 350°F (175°C).

• Bake for 40–45 minutes, until deep golden brown and cooked through (internal temp ~190°F / 88°C).

• If browning too quickly, cover loosely with foil during the last 10–15 minutes.