Heat the olive oil, on medium high heat, in a non-stick pan, add the sausage and saute quickly to render juices. Add the chopped onions and cook until translucent. Once the onions are cooked, add garlic, oregano and tomatoes and cook slowly for 5 minutes. Add the beaten eggs to the pan, and toss in scallions and begin folding together slowly with a rubber spatula. When well blended, season with salt and pepper and serve hot.