Prepare the Dough: Mix warm milk, instant yeast, and granulated sugar in a large bowl and let it sit until frothy—about five minutes. Then add melted butter, room temperature eggs, and salt before gradually incorporating all-purpose flour until a soft dough forms. Knead until smooth and elastic, then let it rise in a warm place until it doubles in size—about an hour.
Make the Filling: While the dough is rising, mix softened butter with brown sugar, espresso powder, and ground cinnamon in a separate bowl until well combined. Set aside the finely chopped dark chocolate for later.
Assemble the Rolls: Roll out the dough on a floured surface into a large rectangle (14x18 inches). Spread the filling evenly across the dough's surface and sprinkle with chopped dark chocolate.
Second Rise: Roll up the dough tightly to create a log shape and slice it into twelve equal pieces. Place the slices into a greased baking dish close together but not touching. Cover and allow them to rise again until puffed—about thirty minutes.
Bake Your Rolls: Preheat your oven to 350°F (175°C). Once the rolls are ready, bake for approximately twenty-five minutes or until golden brown on top.
Prepare and Finish Glaze: Whisk together powdered sugar, milk, vanilla extract, melted chocolate (if using), and espresso powder until smooth; drizzle over warm rolls before serving.