In a stand mixer bowl, combine warmed milk, yeast, and 50g sugar; let stand for 5 minutes until foamy.

Add flour and 4 eggs. Mix with the dough hook on low speed for 5 minutes until a shaggy dough forms.

Add salt, then incorporate softened butter one cube at a time, allowing each to be absorbed before adding the next. Mix on medium-high for 15 minutes until the dough is glossy and pulls away from the sides.

Transfer dough to a greased bowl, cover, and proof at room temperature for 2 hours or until doubled in size.

In a saucepan over medium heat, combine raspberries, filling sugar, cornstarch, and lemon juice. Simmer for 10 minutes until thickened; cool completely to room temperature.

Degas the dough and roll into a 30x40cm rectangle on a lightly floured surface.

Spread the cooled raspberry mixture evenly over the dough, leaving a 2cm border.

Roll the dough tightly from the long edge into a log. Slice the log in half lengthwise to expose the layers.

Twist the two strands together into a braid and place into a greased 9x5 inch loaf pan. Proof for 1 hour.

Preheat oven to 180°C (350°F). Brush the loaf with egg wash and bake for 40-45 minutes until the internal temperature reaches 88°C (190°F).