Preparation

• Vegetable oil for the griddle Using a food processor fitted with the medium grating disk, grate the potatoes and parsnips separately. Put the potatoes in a clean kitchen towel and squeeze out as much liquid as possible. In a large bowl, combine the potatoes, parsnips, scallions, eggs, flour, 2 tsp. salt, and a few grinds of pepper and mix well.

  Generously oil a griddle and heat over medium heat. Working in batches, spoon about 1/3 cup of the mixture onto the griddle at a time to form pancakes. Flatten the pancakes with a spatula (they should be about 1/2 inch thick) and cook until the bottom is well browned and crisped, about 5 minutes. Flip and cook until the other side is well browned, about 5 minutes more. Sprinkle with salt. Serve immediately or keep warm in a low oven until ready to serve.