It sounds fairly strange, no? I had heard of putting eggs in coffee before, mostly from Scandinavian countries where it was used to clarify the brew and generate an amber-coloured cup of coffee with a milder taste. In contrast, Vietnamese egg coffee (Cà Phê Trứng) is anything but a clearer coffee with a mild taste. As it appears in the photo, it is essentially a Cadbury Creme Egg with a hint of mocha.
3 teaspoons of Vietnamese coffee powder (Vietnamese coffee is available on Amazon here: http://amzn.to/17SfPza)
2 teaspoons of sweetened condensed milk
Brew a small cup of Vietnamese coffee. (Vietnamese coffee filters available on Amazon here: http://amzn.to/11zk7lA )
Crack an egg and discard the whites.
Put the yolk and the sweetened condensed milk in a small, deep bowl and whisk vigorously until you end up with a frothy, fluffy mixture like the one above. Add a tablespoon of the brewed coffee and whisk it in.
In a clear coffee cup (we’re going for aesthetics here), pour in your brewed coffee, then add the fluffy egg mixture on top.
Presto. Egg coffee for all!
Photo & recipe shared from: http://www.legalnomads.com/2013/01/vietnamese-egg-coffee-recipe.html