This article is from the Coffee and Caffeine FAQ, by Alex Lopez-Ortiz with numerous contributions by others.
Disclaimer: People prepare cappuccino in many different ways, and in
their very own way each one of them is correct. The following recipe,
which is commonly used in Latin countries, has been tasted by several
of my North-American friends and they unanimously agreed that
cappuccino prepared using this recipe tastes much better than the
standard fare in USA/Canada.
Start with cold milk (it doesn't really need to be ice-cold), use homo
milk or carnation. 2% or skim is just not thick enough (admittedly, it
is easier to produce foam with skim milk).
Place the milk on a special cappuccino glass with a cappuccino basket.
(Cappuccino glasses have a thinner bottom).
Aerate the milk near the top, within 2cm (1 in) of the top. Move the
glass down as the milk aerates. It is a good idea to have an
oscillating motion while aerating the milk.
Aerating the milk in another container, then pouring in a glass and
adding the foam with a spoon is sacrilege.
Anybody who has done so should make a pilgrimage to San Francisco's
Girardelli's. Otherwise entry to heaven will be denied (god, is after
all, Italian. At least the catholic one).
If you need to aerate the milk on a separate container, aerate exactly
the amount of milk required for one cup, so no need to add foam with a
spoon.
Once the milk has been aerated, promptly clean the aerator with a wet
rag. Failure to do so will quickly result in rotten milk flavour
coming from the aerator.
Another warning on similar lines applies to restaurant type coffee
machines: leave the aerator valve open when powering the machine up
and down. When the machine is off a partial vacuum is formed in the
boiler that will suck milk residue into the boiler. This then coats
the inside of the boiler and can cause bad smelling steam until the
boiler is flushed. Some machines have a vacuum bleed valve to prevent
this problem but many don't.
Wait for the steam pressure to build up again (for some cappuccino
makers wait time is near zero, for others it maybe as long as 60
secs).
Prepare the espresso coffee, you may add it directly on to the glass
if possible or use a cup and then pour it from the cup on the milk.
According to Jym Dyer: In Italy, the milk is added TO the espresso,
not the other way around, that way the milk is floating; on top, where
you then add the sugar, and stir it up.
Cappuccino tastes better when is really hot, and has two teaspoons of
sugar. (small teaspoons, like the ones in expensive silverware).
Then accompany said cappuccino with a warm tea bisquet or english
muffin with marmalade, or alternatively with a baguette sandwich or
panini.
 
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