Combine yeast and sugar in a bowl, then slowly pour in the warm water (make sure it's warm like bath water and not hot), stirring everything together. Allow mixture to sit until yeast starts to foam/bubble on top, around 8-10 minutes.
Meanwhile, combine butter and milk over medium-high heat on the stove, stirring occasionally until butter has melted, but making sure not to let them come to a boil. Remove from heat and set aside.
Next, stir flour and salt together in a large bowl and set aside.
Pour melted butter and milk into the bowl with the yeast and stir to combine, then pour the liquid ingredients into the bowl with the flour. Use a wooden spoon to stir mixture together for at least 1 minute, or knead dough with your hands for 2 minutes. The dough will be sticky and that's ok.
Grease a separate large bowl with a bit of coconut oil, and then transfer dough into that bowl. Place a towel over the bowl, and then put the bowl in the oven and allow the dough to rise and double in size, about 1 hour.
Right before the hour has passed, make the filling. Start by melting butter, and setting it aside, then combine cinnamon, cocoa and espresso in a separate bowl and set them aside as well.
Remove dough from the oven (it should be double in size, or at least close) and stir in an additional 1/3 cup flour. This will make the dough less sticky and easier to roll out.
Next, set up your work space. Flour a baking mat (or your kitchen table), and then use a rolling pin to roll the dough out into a rectangle, being careful not to let the dough get too thin. Brush the dough with the melted butter, leaving about a 1/2 inch border around the edges. Next, sprinkle the sugar on top, then the cinnamon, cocoa and espresso mixture, using your hands to press everything gently into the dough.
Starting with the long side of the rectangle, gently roll the dough up into a log. Then, using a knife, cut the log into 1" cinnamon rolls, placing them cut side down into a baking pan.
Once all the rolls are cut, cover the dish back up with the towel and place the dish in the oven, allowing the rolls to rise for 30 minutes.
Once the 30 minutes have passed, remove rolls from the oven (but keep the towel on top) and preheat the oven to 350°.
Bake rolls for approximately 25-30 minutes, or until dough has set and cinnamon is bubbling.
While rolls are baking, make the icing by combining the powdered sugar and milk together with an electric mixer until icing is smooth.
Once rolls are done, drizzle icing over top.