How to Make It
Preheat the oven to 450°. Generously brush the bottom and sides of a 9-inch glass pie plate with some of the melted butter; set aside.
In a small bowl, combine the bacon drippings and the rest of the melted butter. In another bowl, combine the flour, Parmesan cheese, salt, ginger, mustard, pepper, thyme, rosemary and nutmeg; spoon about 1/4 cup of this mixture onto a small plate.
Pick out the prettiest and most uniform turnip slices. Dip one into the bacon fat and butter, then press one side into the seasoned flour on the plate. Lay the slice, floured side up, in the center of the pie plate. Repeat dipping and placing the most uniform slices, overlapping them slightly and working out from the center in concentric rings, to cover the bottom and sides of the pie plate.
Continue layering the remaining turnip slices in slightly overlapping concentric rings. Brush each layer all over with the remaining bacon fat and butter and scatter a little of the remaining seasoned flour evenly on top, until all the turnips have been used.
Brush bacon fat and butter on the shiny side of a 9-inch square of aluminum foil and place, buttered side down, on top of the turnips. Place a heavy 8- or 9-inch skillet on top and press firmly; fill the skillet with pie weights or dried beans.
Bake the turnips in the middle of the oven for 30 to 35 minutes, until the bottom and sides are richly browned. (Set a pan on the rack below to catch any juices.)
Remove from the oven, lift off the skillet and peel off the foil. With a thin spatula, carefully loosen the turnip cake around the edges. Let cool for 5 minutes, then invert onto a heated serving plate. Cut into wedges and serve at once.