Heat half the olive oil in a heavy skillet over medium heat. Add the onion and cook until soft. Add the garlic, and cook for one additional minute. Add the spinach and stir until wilted. Turn off heat and transfer to a large bowl.
Add the potato, oregano, tomatoes, olives, artichokes, and peppers to the medium mixing bowl and stir. Add the eggs and flour, and season with salt and pepper.
Form the mixture into patties. Or, if making as an entrée, form into two large cakes.
Heat the remaining olive oil in a skillet and cook the cakes until crispy and browned on both sides. Slice cakes into individual servings and serve hot.
If desired, top with an olive tapenade or chopped fresh herbs.