Bring a medium pot of salted water to a boil. Add sweet potatoes, and cook until they can be easily pierced with a fork but still offer some resistance, 3 to 4 minutes. Drain, and rinse under cold running water. Refrigerate until completely chilled, about 1 hour.
Heat 2 tablespoons olive oil in a large skillet over medium heat. Add onions, and saute, stirring occasionally, until onions are tender and golden brown, about 20 minutes. Transfer onions to a small bowl, and set aside.
Pour remaining 4 tablespoons olive oil into the skillet, and place over medium-high heat. Add potatoes, and cook, stirring occasionally, until golden brown, about 8 minutes. Add reserved onions, and cook 2 minutes. Toss in parsley, and adjust the seasoning to taste with salt and pepper. Serve immediately.
i made this for easter last year and have been asked to make it 10 more times since! It's light and fun and a unique twist on a regular potato hashbrown. I have been asked for the recipe over and over!