Sounds like what we make at home, although we use the whole egg not just the whites.
Basically we get it too fluff and rise right up by getting the old electric beater out and beating it with milk until its light and fluffy and then through in the onions and capsicums etc is and whisk it a little more. Then pour it into an already hot pan and let it sit until the bubbles start popping. At that point we through it under the grill with a little cheese and leave it until its set and golden brown on top. It tends to rise the most when under the grill...sometimes more than doubling in height. Mmm...soooo fluffy...sooo...light...Mmm...