1. To make the horseradish cream, in a small bowl stir together the sour cream and horseradish. Set aside.
2. To make the parsnip fritters, in a medium bowl combine the parsnips, flour, scallions, salt and pepper. Toss, then add the eggs and mix.
3. In a large nonstick skillet over medium-low, heat 2 tablespoons of the oil. Working in batches, use a 1/4-cup measure to scoop mounds of the parsnip mixture into the skillet. Flatten each mound into a 3-inch patty, then cook until golden-brown on both sides and tender in the center, about 4 minutes per side. Set aside and cover to keep warm while you cook the remaining patties in the remaining 2 tablespoons of oil.
5. Serve topped with a dollop of horseradish cream.