Melt oil in hot skillet.
Add diced onion and cook until soft, about 4 minutes.
Add the swiss chard and allow it to cook down, about 3 minutes.
Season with oregano, sea salt, and pepper.
Add the beaten eggs to the vegetables.
Tilt the pan so the eggs spread out evenly.
Use a rubber scraper or spatula to turn the eggs over so that they don’t harden and burn.
Scramble the eggs for 2 to 3 minutes to desired consistency.