Begin by gently warming the milk to about 110°F (43°C) and dissolving the active dry yeast in it for 5-10 minutes until frothy.

In a stand mixer, combine all-purpose flour, unsweetened cocoa powder, brown sugar, and salt. Gradually mix in the egg, softened butter, and the yeast mixture, kneading for about 3 minutes until the dough is soft and slightly sticky.

Cover the bowl with a clean kitchen towel or plastic wrap and let the dough rise in a warm environment for 1.5 to 2 hours, or until it has doubled in size.

While the dough is rising, prepare the filling by mixing together brown sugar, cocoa powder, ground cinnamon, and vanilla extract in a medium bowl.

Once the dough has risen, turn it out onto a lightly floured surface and roll it into a rectangle approximately ¼ inch thick. Spread softened butter evenly over the surface, then sprinkle the filling mixture generously across the top.

Roll the dough tightly into a log, sealing the edges, and slice into 9-11 pieces for perfectly shaped rolls.

Place the sliced rolls in a greased baking dish, ensuring they are spaced apart for rising. Cover them with a towel and allow them to rise for another 30-60 minutes.

Preheat your oven to 350°F (180°C). Bake the rolls for about 20 minutes or until they are puffed up and lightly golden brown on top.

Whisk together powdered sugar, cocoa powder, and heavy cream in a small bowl until smooth and creamy.

Drizzle the chocolate glaze generously over the rolls while they’re still warm.