Warm up the milk. Pour off 250 ml and set aside. Add the cream to the rest of the milk and dissolve the Nutella completely while continuing to heat. Stir in cocoa powder and cinnamon.
Divide the drink between 4 latte macchiato glasses, filling the glasses only 3/4 full. Froth the 250 ml milk from the beginning and use a spoon to spread the foam over the cocoa. Sprinkle with a little cocoa powder if you like.
If you want to vary a bit, add a dash of coconut milk while heating. This gives the cocoa an exotic note.