Warm 400 ml whole milk until lukewarm, about 38–43°C.

Stir active dry yeast, granulated sugar, and about 3 tablespoons of plain flour into the warm milk.

Rest the yeast mixture for 5–10 minutes until foamy.

Combine the remaining plain flour, salt, 1 egg, and activated yeast mixture in a large mixing bowl.

Knead the dough until the ingredients form a cohesive mass.

Add cubed unsalted butter to the dough.

Knead for 8–10 minutes until the dough is smooth and elastic.

Divide the dough into two equal portions.

Knead cocoa powder into one dough portion until evenly brown.

Cover both dough portions and let them rise in a warm place until doubled, about 60 minutes.

Shape both dough portions into equal small balls.

Arrange the plain and cocoa dough balls alternately in the loaf pan.

Cover the shaped loaf and let it rise again for about 30 minutes.

Preheat the oven to 180°C / 356°F.

Whisk 1 egg with 10 ml whole milk to make the glaze.

Brush the glaze evenly over the risen loaf.

Bake at 180°C / 356°F for about 30–35 minutes until golden brown and fully baked.

Cool the pogača on a wire rack before slicing.