In a small bowl, combine warm milk with granulated sugar, stirring until dissolved. Sprinkle the active dry yeast over the mixture and let it sit undisturbed for 5-10 minutes until frothy.

In a stand mixer, combine the all-purpose flour and salt. Add the activated yeast mixture, softened unsalted butter, and a large egg. Mix on low speed, then increase to medium and knead for 7-8 minutes.

Transfer the kneaded dough to a greased bowl, turning to coat lightly. Cover and let it rise in a warm place for about 1-1.5 hours, or until doubled in size.

Punch down the risen dough and roll it into a rectangle about ¼-inch thick. Brush with melted butter and sprinkle with mozzarella, Parmesan, minced garlic, and herbs.

Roll the dough into a tight log, slice it down the middle to reveal swirls, then twist and shape into a spiral in a greased baking pan. Let it rise again for 30-40 minutes.

Preheat oven to 350°F (175°C). Brush the top with egg wash and bake for 30-35 minutes until golden brown and hollow-sounding.

Cool in the pan for 10 minutes, then transfer to a wire rack to cool completely before slicing.