In a large mixing bowl, combine the milk, sugar, and yeast. Stir with a wooden spoon or dough whisk, then let it sit for 10-15 minutes, or until the yeast becomes bubbly.
Add the butter and eggs to the mixture and stir again.
Next, add the salt and 2 cups of flour, mixing well. Gradually add more flour, ½ cup at a time, until the dough begins to form a ball and pulls away from the sides of the bowl.
Turn the dough out onto a floured surface and knead for 3-5 minutes, adding more flour if necessary. The dough should feel soft and slightly tacky, but not sticky.
Place the dough in a greased bowl, cover with a cloth, and let it rise until it has doubled in size, about 1½ hours.
Once the dough has risen, punch it down and roll it out onto a floured surface. Aim for a rectangle shape, about 14x18 inches.
Spread the room temperature butter evenly over the dough, leaving about ½ inch along the bottom edge free to help seal the roll.
Sprinkle the brown sugar evenly over the butter, taking care not to tear the dough. Then, sprinkle the cinnamon, black cocoa powder, and crushed Oreo cookie crumbs on top.
Starting from the long 18-inch edge, carefully roll the dough up into a log. Once rolled, gently squeeze both ends to compact the dough. This helps bring the dough back together if it stretches out during rolling.
Cut the dough into 12 rolls. For even-sized rolls, make small markings along the dough first as a guide.
Place the rolls in a greased 9x13-inch pan (or two 9-inch round pans, with 6 rolls in each). It’s fine if the rolls are touching. If you plan to bake the rolls the following day, refer to the notes below for instructions.
Cover the rolls and let them rise in a warm spot until they double in size, about 45-60 minutes. If needed, place them in the oven with the light on to help with warmth, but remember to remove them before preheating the oven.
Preheat the oven to 375°F.
Bake the rolls for 14-18 minutes, or until the tops are golden brown. While they cool, prepare the frosting.
To make the frosting:
In a bowl, mix together all frosting ingredients until smooth and creamy. Adjust the consistency by adding more powdered sugar or milk, as needed.
Allow the rolls to cool slightly before frosting them. Once frosted, sprinkle with additional crushed Oreo cookie crumbs.