Step 1: Heat a skillet and spray with oil. Add the egg whites, torn spinach, onion and feta on top. Heat until you can see the egg bubbling and a spatula lifts the edge completely.
Step 2: If you’re brave or talented, you can simply flip the omelet by tossing the skillet. However, I used 2 spatulas on either side to lift and flip. Cook another 2-3 minutes over medium heat, until egg is full cooked and beginning to brown.
The feta delivers nice little pockets of salty cheesiness, the green onion is still slightly crunchy and flavorful and the spinach is perfectly wilted. Enjoy with your favorite breakfast beverage. As always, substitute whatever veggies and/or cheese you prefer.