Blend all the ingredients until you achieve a silky-smooth consistency.
Refrigerate the coffee smoothie for one hour before serving it chilled. Alternatively, you can use ice cubes if you want to enjoy the smoothie right away.
Notes
If you're an espresso enthusiast, feel free to substitute a shot of espresso for regular coffee. Just ensure that you add enough water to reach a total of approximately 300 ml (a generous cup) of liquid.