Combine warm milk, active dry yeast, and 1/4 cup granulated sugar in a bowl. Let sit for 5-10 minutes until frothy.

Mix bread flour and salt in a large bowl. Add egg yolks, vanilla extract, and softened unsalted butter, then pour in the frothy yeast mixture. Stir until well combined.

Knead the dough on a floured surface until smooth and elastic, about 10 minutes. Let rise for about 1 hour or until doubled in size.

Preheat oven to 350°F (175°C).

Mix diced apples, brown sugar, cinnamon, allspice, and nutmeg in another bowl.

Beat cream cheese, 1/4 cup granulated sugar, and 1 teaspoon vanilla extract in a separate bowl until smooth.

Roll out the dough, spread the cream cheese mixture, then spoon the apple mixture on top. Roll tightly and slice into individual buns.

Mix melted unsalted butter, 1/4 cup brown sugar, 1 teaspoon cinnamon, and all-purpose flour until crumbly. Sprinkle over the buns.

Bake for 18 minutes or until golden brown.