I got this recipe from Alton Brown, who extols it as
almost as good for making cocoa as when you make the syrup yourself. It has the benefits of being considerably less expensive than packaged instant coca, tasting better, and the comfort of knowing what's in it.
Instant Cocoa Powder2 cups of powdered sugar
1 cup of Dutch-processed cocoa*
2-1/2 cups of dry milk powder
2 tsp corn starch
1 tsp salt
1 pinch cayenne pepper (which I have never had the guts to try)
Mix all the ingredients together thoroughly and store in an air-tight container. (I use a 3-lb coffee can and a wire whisk.)
To make cocoa, fill a mug about 1/3 full with the powder mixture and then add hot water or milk. (In my microwave, 83 seconds for 12 ounces of milk works nicely. 90 seconds will boil the milk, which you don't want to happen.) Stir thoroughly and with great reverance while chanting praises to the god of chocolate.
I found Alton Brown's recipe to be too sweet for my taste, especially when mixed with milk, so I usually increase the amount of Dutch cocoa powder by about 1/3 of a cup.
A layer of little marshmallows floating on top adds sweetness, interest, and (most important) insulation that keeps your cocoa warm. It also makes an interesting mess in the cup that can be an adventure to clean if you let it harden.
For more fun and a Mexican flavor, add a stick of cinnamon as a stirrer.
Try sprinkling some of the instant cocoa powder on Haagen-Dazs chocolate ice cream. Sinfully good.
*Hershey's makes an excellent Dutch cocoa powder. It comes in the same kind of can as their regular cocoa but it might be hard to find in local grocery stores. Dutch cocoa is less acidic and darker than regular cocoa and has a stronger chocolate flavor.
Warning: This stuff is so good that it is contraindicated by moral statute in the 14 northeastern states and the Distrit of Columbia. It is also addictive and habit-forming. Known side effects include a wistful longing for more cocoa and in some rare case, uncontrollable foodgasms. If you experience these side effects, increase dosage until you don't care. This product is also effective as a solid rocket fuel when mixed with potassium permanganate and an aliphatic resin binder.