In a large saucepan, bring 2 quarts salted water to a boil and add parsnips. Return water to a boil and boil parsnips 3 minutes. Drain parsnips well. In a food processor fitted with coarse grating disk or on a hand grater, grate parsnips and onion coarsely.
Line a baking sheet with waxed paper. In a bowl, stir together parsnips, onion, and egg and stir in spices and salt. Add flour, stirring until just combined, and form mixture into eight 1/2-inch-thick cakes (each about 3 inches in diameter), transferring them as formed to prepared baking sheet.
In a large heavy skillet heat oil and butter over moderately high heat until foam subsides and saute pancakes in 2 batches until golden, about 5 minutes on each side, transferring them as cooked to paper towels to drain. Pancakes may be kept warm 15 minutes in a 200 degree oven F.