01 - In a small bowl, mix the cocoa powder, granulated sugar, and salt until evenly distributed.
02 - Add 2 to 3 tablespoons of milk to the dry mixture and stir until a smooth paste forms, free of lumps.
03 - Pour the rest of the milk into a large glass or pitcher, then add the cocoa paste and vanilla extract; whisk thoroughly until fully combined and smooth.
04 - Serve cold over ice, or gently warm in a saucepan on low heat for a hot beverage; stir before serving.