Whisk cocoa and sugar with a small part of the measured milk into a paste. Look for dry pockets at the saucepan edges before adding the rest. This makes a more useful starting mixture than chasing dry cocoa across a full pan of milk. Warm gently and stir, following the no-boil method.
Set the marshmallows flat while dotting their faces so they do not roll under the skewer. Use only the melted chocolate needed, then float one ghost face-up on each mug. Have heatproof mugs ready before finishing the cocoa and let the liquid cool to a comfortable drinking temperature. The marshmallow will soften, so decorate at serving rather than expecting its face to last through a long holding period.
Timing and servings are estimates. Equipment, ingredients and portion sizes affect the result.
