To make chocolate milk, combine all the aforementioned ingredients together. Take a glass and pour the milk into it. Whilst blending the mixture with an immersion blender or spoon, gradually add the milk into the glass. It would be advisable to use an immersion blender to avoid clumping of the cocoa powder.
Add a teaspoon of powdered sugar to the glass of cocoa powdered milk. You can either have the chocolate milk immediately or refrigerate it and have it chilled later.
In case you refrigerate it, ensure you stir the milk or shake it well before drinking it. This helps avoid the cocoa powder and sugar to settle at the bottom of the glass.