In a large bowl, dissolve yeast in warm milk. Stir in granulated sugar, eggs, 6 tablespoons softened butter, and salt.

Mix in cocoa powder and 3 cups of the flour, mixing and adding more flour as needed until mixture forms a soft dough.

Turn dough out onto a lightly floured surface and knead until dough is smooth, about 6 minutes. Cover and let rise for 1 hour.

Mix together 2 tablespoons softened butter, brown sugar, and cinnamon.

When dough has risen turn onto floured surface and roll out to a large rectangle. Sprinkle sugar mixture over dough, leaving a 1/2-inch border all around. Top sugar mixture with mini chocolate chips.

Roll up, starting with a long side, and pinch seams together to seal. Cut into 12 slices. (Keep a towel handy to clean knife after cuts, if needed.) Place rolls in a greased 13x9-inch baking pan. Cover and let rise until puffy, about 30 minutes.

Bake at 350°F for 30 minutes. Remove from oven and let cool slightly.

As the rolls cool, whisk together powdered sugar and milk to create icing. Add more milk or sugar to get the consistency you prefer. Pour over the tops of the cinnamon rolls and serve.