Preheat a ceramic pan filled with water on medium heat.

While the pan is preheating, warm the vegetables in the microwave.

Empty the water from the pan.

Reduce the heat to medium-low.

Add the whisked egg whites.

While shaking the skillet back and forth over the heat, use a rubber spatula to stir.

Run the spatula across the edges to loosen the omelet from the pan.

Add heated vegetables to one side of the omelet.

Lift the omelet right side over left in one motion.

Lightly seal the edges by pressing them down with the spatula.