Prepare the espresso a few hours in advance. Add 1 teaspoon sugar and 2 teaspoons cocoa and stir well. If you want to do more than one, you can put it all in one container. Let cool and then put in the fridge for a few hours.
Just before serving:
Whip the cream. Mix the espresso mixture well again.
Pour into the glass. If you have several servings, distribute evenly between the glasses. Fill up to halfway with cold milk and stir. Now the ice cream too. Possibly add a little more milk, depending on how full it is.
Finally, sprinkle a whipped cream on top and dust with a little cocoa.
And then just enjoy. It tastes like coffee and is wonderfully chocolaty.