Do a VERY quick blend in the blender of the ice cube ingredients. (Whipping cream will froth easily and you want to avoid this as much as possible.)
Pour mixture into a 16-cube ice cube tray and sprinkle ground cinnamon on top (more or less to taste), then freeze for at least 1 1/2 hours.
To make the liquid:
Blend all ingredients in the blender.
To assemble the coffees:
For each glass (the recipe makes two glasses), add eight ice cubes. Pour 1 1/2 cups of the liquid on top.
Sip slowly, giving the ice cubes time to melt and infuse more flavor into the coffee. (See notes if you don't want to wait long for the ice cubes to melt.)
Some people like to add hot coffee to their coffee cubes to make them melt faster. I prefer to let my ice cubes melt slowly (which makes the coffee extra-chilled), but if you want a faster melt, warm the almond milk mixture before pouring it over the ice cubes.