Heat a non-stick 8 inch skillet over med heat for 2/3 minutes.
In a bowl, wisk the egg whites with the seasonings of your choice until frothy
Wisk in the cheese of your choice.
Saute your vegetables in a separate pan to get a head start on cooking.
Fold in sauteed vegetables into your mixture.
Lightly spray your olive oil on the pan and pour in mixture.
As soon as the edges start to set, reduce the heat to medium-low.
Gently lift the edges and move the pan so the runny liquid moves to the edges from the center to promote even cooking.
When the top of the omelet is not runny anymore but still a bit wet, carefully flip in half on itself. Press the top with the spatula to insure center is done. You can flip it easier over again to continue cooking.
Slide out of the pan onto a plate, sprinkle with extra cheese or seasonings.
Add sliced tomatoes on the side.