In a small pan add milk, cocoa powder, sugar, instant coffee granules, cinnamon, nutmeg and the juice from 3 clementine oranges.
If you like the taste of cloves, an option is to add just a super small pinch of ground cloves.
Heat the mixture on medium heat while constantly stirring. If the mixture starts to boil, turn the heat down just a bit.
Continue stirring until all of the ingredients are combined and the mixture starts to thicken (about 6 minutes).
Then turn the heat off, move the pan off of the hot burner and let the mixture cool for about 15 minutes. Stir it a few times while it’s cooling.
Fill two serving glasses with ice.
Pour the café mocha in a small pitcher or pouring measuring cup so it's easier to pour into the serving glasses (instead of pouring it from the pan).
Pour the café mocha into serving glasses leaving about 2 inches of space from the top for the half and half (or cream if preferred).
To the glasses, add half and half, or cream to the café mocha.
It looks pretty in the glass when serving if the half and half (or cream) is not stirred so the drink has a creamy layered look to it.
Add a few more ice cubes if there is room in the glass to top it off.
Garnish with a segment of clementine orange and serve cold.