DEFINITION: Omelette

In cuisine, an omelette or omelet is a dish made from beaten eggs quickly cooked with butter or oil in a frying pan, sometimes folded around a filling such as cheese, vegetables, meat (often ham), or some combination of the above. To obtain a fluffy texture, whole eggs or sometimes egg whites only are beaten with a small amount of milk or cream, or even water, the idea being to have "bubbles" of water vapor trapped within the rapidly cooked egg. The bubbles are what make the omelette light and fluffy.

Omelettes may be only partially cooked on the top side and not flipped, even prior to folding.

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http://en.wikipedia.org/wiki/Omelette