Heat oil in a 10" or 12" nonstick skillet over medium heat.
Add spinach and cook until wilted; stir in the sun-dried tomatoes and heat through, about 2 minutes.
Stir the eggs into the spinach and sun-dried tomatoes and add the garlic powder, oregano, and a little black pepper.
Using a silicone spatula, stir the eggs until cooked through, about 4-5 minutes.
Remove the pan from the heat and stir in the feta.
Divide the eggs between the English muffins and serve hot.
