Warm the 2 cups of whole milk in a saucepan over medium heat until tiny bubbles form around the edges. Don't let it boil.
In a small bowl, whisk together the cocoa powder, maple syrup, and salt to prevent lumps.
Gradually add the cocoa mixture to the warmed milk, stirring continuously with a whisk until fully combined.
Remove from heat and stir in the vanilla extract.
If using protein powder, mix it in well at this stage. Use a blender if needed to ensure it's fully incorporated.
Pour into tall glasses and top with whipped cream and a sprinkle of cocoa powder if desired.
