Tortilla De Patatas
Heat the olive oil in the same large skillet. Pour in the egg and potato mixture into the skillet and spread the potatoes out evenly. Cook until the underside is set and lightly brown. Occasionally give the skillet a gentle shake to move the tortilla around. Invert the tortilla onto a plate, then gently slide back into the skillet. Cook until the underside is also set and browned, also occasionally shaking the skillet.