This recipe is flexible, so tweak it till you find what you like best!
Measure one cup of milk.
Powdered milk works, too, if that's all you have.
Add one to two Tablespoons of sugar,
one to two Tablespoons of cocoa,
1/4 teaspoon vanilla,
and a pinch of salt.
Stir till somewhat smooth, then microwave for about a minute and a half; stir a little more, and enjoy! =)