Serves 3 to 4 15 minutes prep time; 45 minutes oven time Excellent hot or at room temperature.Reheats well. Whether you call them frittatas or oven omelets, baking eggs with a sauté or filling is much easier than fussing with a traditional omelet. Instead of the gymnastics involved in cooking and rolling a perfect folded omelet out of the pan, you put everything together, put it in the oven, and set a timer. With its cheesy greens and garlic, this oven omelet comes o< more like a pizza than an omelet. The shards of tart green apple are totally unexpected and a great accent. This is portable food— good for potlucks, boat rides, and office lunches. 1 bunch (5 stalks) Swiss chard, stems and leaves separated Good-tasting extra-virgin olive oil 2 medium onions, cut into 1-inch dice Salt and fresh-ground black pepper 1 large garlic clove, minced ¼ cup water ½ large Granny Smith apple, peeled, cored, and cut into ½-inch dice 5 large eggs ¾ cup milk ⅛ teaspoon fresh-grated nutmeg ⅛ teaspoon salt ⅛ teaspoon fresh-ground black pepper⅛ teaspoon fresh-ground black pepper 1 cup fresh-grated Parmigiano-Reggiano, Asiago, or Fontinella cheese 1 cup shredded Muenster or Monterey Jack cheese 1. Preheat the oven to 350°F. Chop the chard stems into 1-inch pieces, then chop the leaves the same way. Film a 10-inch skillet (with an ovenproof handle) with oil, and heat over medium-high heat. Add the onions, chard stems, and a little salt and pepper. Sauté until the vegetables are golden brown. 2. Stir in the garlic and chard leaves in two batches. (As the ?rst batch wilts, add the second.) Add the water, and stir over mediumhigh heat until the leaves look like cooked spinach and the liquid has evaporated. Then stir in the apple and remove the skillet from the heat. 3. In a bowl, beat together the eggs, milk, nutmeg, salt, pepper, and ⅔ cup of each of the cheeses. Pour the mixture over the cooked greens. Sprinkle with the remaining cheeses, cover with foil, and bake for 30 minutes. Uncover and bake for 10 to 15 minutes more, or until a knife inserted in the center comes out with only a few bits of creamy egg and cheese clinging to it. 4. Let the omelet stand for 5 to 10 minutes before cutting it into wedges. Variation SPANISH PAPRIKA–POTATO OVEN OMELET Substitute for the chard 1 medium to large red-skin potato, sliced as thin as potato chips; and use only 1 medium onion, sliced into thin rings. Add them to the oiled skillet as described, sprinkle with salt and pepper, and sauté until the potatoes are tender. Remove from the heat. Sprinkle the potatoes with 1 tablespoon mild Spanish paprika. As directed above, blend together the eggs, milk, and cheeses, omitting the nutmeg. Pour the mix into the skillet, lifting the potatoes so the custard covers the bottom of the pan. Sprinkle with the remaining cheeses, cover with foil, and bake as described above