In a large mixing bowl, combine yeast, flour, sugar and salt. In a microwave-safe bowl, melt the butter in the microwave together with the milk and water. This mixture should be within 105-115 F. Reheat briefly in the microwave or cool as needed to attain the required temperature.
Add the butter mixture to the dry ingredients in the bowl. Mix together using a wooden spoon. Add the egg, then add the remaining flour little by little, mixing after each addition. Only add sparingly-you may not need the entire 1/2 cup. You only need to see the dough gather in the center and cleaning the sides of the bowl. After this consistency is achieved, stop adding the flour.
Turn the dough over on a floured board. Knead the dough, adding a little flour from time to time just to avoid the dough from sticking to the board or to your hands. From sticky and shaggy, the dough will be smooth, elastic and can stretch thinly.
Let the dough rest for ten minutes. Roll it into a 14 x 8 inches rectangle. Spread the Nutella over the surface. Combine brown sugar, cinnamon and cocoa and sprinkle this mixture over the hazelnut spread.
With the long side nearest you, roll the dough into a tight log. Use a sharp knife to cut the log into 10-11 portions. Arrange them on a lightly greased 9 inch round cake pan with about half an inch of space in between. Press the rolls down so that they are about the same height.
Let the dough rise: Cover the rolls with plastic wrap and let rise at room temperature for 12 hours OR pre-heat oven to 200 F. Once the oven reaches the temperature, turn off heat and place the rolls inside with the door closed. Let rise for 60-90 minutes.
Preheat oven to 375 F. Bake the rolls for 15-20 minutes or until the lightly golden. Pour Nutella glaze over the rolls. Store leftovers at room temperature in a tightly covered container.