Adapted from “Mastering the Art of Southern Cooking” by Nathalie Dupree and Cynthia Graubart.
4 tablespoons unsalted butter, divided 1 medium onion, chopped 2 garlic cloves, minced 1 bunch turnip greens, stems removed, leaves chopped, then blanched in boiling water or microwave 3 ounces smoked country ham, diced 2 cups water 1 teaspoon salt 1/2 teaspoon freshly ground black pepper 1 cup cornmeal 1 cup milk 4 large eggs, separated 1/4 cup freshly grated Parmesan cheese 1/4 cup grated Swiss cheese
Preheat oven to 350 degrees. Butter a 2-quart soufflé dish (or deep, round casserole dish).
In a medium skillet, melt 2 tablespoons butter over medium heat. Add the onion and cook until soft, 5 to 7 minutes. Stir in the garlic, greens, and ham, and set aside.
Bring water, salt, and pepper to the boil in a medium saucepan over moderately high heat. Add the cornmeal in a steady stream, whisking constantly. Reduce heat to medium-low and cook 1 to 2 minutes, whisking or stirring with a wooden spoon or electric hand mixer, until the sauce base is very thick (the consistency of mashed potatoes) and almost comes together in a ball, leaving the bottom of the pan clean.
Remove from the heat and beat in the remaining butter and the milk with a whisk, wooden spoon or electric hand mixer. Beat in the egg yolks. Stir in the reserved greens and ham mixture, and the cheeses.
Beat the egg whites in a separate, clean bowl until stiff but not dry. Stir a fourth of the egg whites into the cornmeal and greens batter to lighten it, then fold the batter into the remaining whites.
Pour the batter into the buttered dish and bake in the middle of the oven for 50 to 55 minutes, until puffed and lightly browned. It will be soft in the center and crusty around the edges. Serve immediately.