preheat the oven 170 c prick the potatoes all over with a fork and bake for 1 hour or until softcooking a spray a frying pan with the cooking spray and stir-fry the spring onions until just tender and golden.cut the potatoes in half Earley scoop out the flash into a large bowl.Add the milk and mash together until you have a smooth blend.stir in the spring onions Andy tomatoes and season. in a clean, grease-free bowl,Wickes the egg whites until stiff and fluffy and then fold carefully Into the potatoes Mixture with the grated cheese.place the potato skin on a baking tray and refill them with the potato mixture, piling up high.bake for 10-15 min, until golden and hot. serve immediately.