In a large mixing bowl, combine the all-purpose flour, granulated sugar, yeast, and salt. In a separate bowl, whisk together warm milk, melted butter, and beaten egg. Pour the wet ingredients into the dry, mixing until a shaggy dough forms. Knead on a floured surface for about 5-7 minutes until smooth and elastic, then place in a greased bowl and cover. Let rise in a warm area for 1-1.5 hours, until doubled in size.

While the dough rises, prepare the filling by mixing cocoa powder, espresso powder, granulated sugar, and cinnamon until well combined. Once your dough has risen, roll it out into a rectangle about 14x10 inches.

Spread softened butter over the rolled-out dough, then evenly sprinkle the filling mixture across. Add chocolate chips on top of the filling and tightly roll the dough into a log shape, sealing the edges.

Use a sharp knife to slice the dough log into 12 equal pieces, about 1.5 inches wide. Place the rolls cut-side up in a greased baking dish, cover with a towel, and let rise for another 30-45 minutes.

Preheat your oven to 350°F (175°C). Once the rolls have risen, bake for approximately 25 minutes until golden-brown. Allow cooling in the baking dish for about 10 minutes.

Prepare the glaze by mixing powdered sugar with milk until smooth and pourable. Drizzle the glaze over the slightly cooled rolls, allowing it to set before serving.