Heat the oven to 375 degrees. Warm the oil in a large skillet. Add the potatoes and cook over medium high heat until browned on the edges and soft in the center. Add the garlic and season with salt after the potatoes have been cooking for 2 minutes. Stir in the turnip greens and cook until wilted and tender, about 3 minutes.
Season the eggs with salt and pepper. Pour the eggs into the pan, sprinkle with the cheese and transfer to the oven. Bake until the frittata is just set, about 10 minutes. Let cool for 10 minutes, then slice and serve.
Before starting Food52 with Merrill, I was a food writer and editor at the New York Times. I've written several books, including "Cooking for Mr. Latte" and "The Essential New York Times Cookbook." I played myself in "Julie & Julia" -- hope you didn't blink, or you may have missed the scene! I live in Brooklyn with my husband, Tad, and twins, Walker and Addison.