Wash and peel the sweet potatoes. Cut into medium size pieces. Coat with oil, oregano, salt and pepper. Place them with some oil in a frying pan over medium heat and cook till potatoes go soft and wilted.
To bake, preheat oven to 180 C. Place potatoes in a glass or non-stick baking dish, and toss to coat. Sprinkle with oregano, salt and pepper (to taste).
Bake in preheated oven for 60 minutes or until soft.