Smoky Sauce: In a medium mixing bowl combine the sour cream, parsley, paprika, vinegar and garlic. Mix until well blended, and then taste to check the seasoning. Season with salt and pepper.
For the hash browns: Grate the potatoes using the large holes of a box grater. Place the grated potatoes on a clean dish towel and squeeze out the excess water.
In a large mixing bowl combine the grated potatoes, onions, parsley, oregano, salt and pepper, and give it a good stir.
Heat the oil in a large nonstick saute pan over medium heat. Using a 1/4 cup measuring cup, scoop out the potatoes and place in the hot pan. Fill the pan with 4 or 5 potato scoops, making sure not to overcrowd the pan. Using a spatula, flatten out the potato portions. Cook until golden brown, about 3 minutes. Flip and continue to cook on the other side until golden brown and crispy, about 3 minutes. Drain the hash browns on paper towels, sprinkle with salt, and repeat the process for the remaining potatoes. Serve with the smoky sauce on the side.