In a stand mixer bowl, combine warm milk and yeast. Let sit for 5–7 minutes until foamy. Add sugar, eggs, salt, vanilla, and flour. Mix until dough begins to form.

Add softened butter one tablespoon at a time, mixing until fully incorporated. Knead for 7–8 minutes until smooth and slightly sticky.

Transfer dough to a greased bowl, cover, and let rise for 1 to 1.5 hours.

In a saucepan, melt butter and add diced apples. Stir in brown sugar, cinnamon, nutmeg, lemon juice, and cornstarch.

Cook 5–8 minutes until apples soften and the mixture thickens. Let cool completely—this prevents a soggy babka.

Punch down the risen dough and transfer to a floured surface.

Roll into a rectangle roughly 12×16 inches. Spread the cooled apple filling evenly across the surface, leaving a small border.

Roll up the dough tightly (like cinnamon rolls). Slice the log lengthwise so you have two long strands with exposed layers.

Twist the strands together, keeping the cut sides facing up for maximum swirl effect.

Place the twisted dough into a parchment-lined loaf pan.

Cover the pan and let the babka rise 30–45 minutes until slightly puffy.

Bake at 350°F (175°C) for 35–40 minutes, or until golden brown and cooked through.

While the babka bakes, heat sugar and water until dissolved.

Brush the warm loaf with syrup after baking—this adds shine, moisture, and bakery-style flavor.