Melt the chocolate in a double boiler gently until smooth. (Or gently in the microwave)
Carefully pour some chocolate into the mold and use a pastry brush to evenly brush the bottom and sides. Don't pour too much or your bombs will be too thick.
Pop in freezer 5-8 minutes until the chocolate is firm.
Add some cocoa powder (1/3 packet) and load in the mini marshmallows.
Pour on another layer of chocolate to cover the filling.
Push the stick into the melted chocolate and return to the freezer until set.
Remove from molds.
Place in a mug and pour steaming hot milk over it!
If desired, add a drizzle of chocolate and lots of sprinkles!