Food & Cooking Recipes Breakfast & Brunch Recipes Potato and Onion Frittata 4.2 (27) 14 Reviews By Martha Stewart Test Kitchen Martha Stewart Test Kitchen The recipes developed by our test kitchen team have undergone a rigorous process of development and testing, ensuring that every element is optimal, from ingredient amounts to method and cooking time. This process includes triple-testing recipes to ensure they meet our high standards. The many stellar cooks and food editors who have been part of our team include Sarah Carey, Lucinda Scala Quinn, Jennifer Aaronson, Shira Bocar, Anna Kovel, Greg Lofts, Riley Wofford, Lauren Tyrell, and Lindsay Leopold. Editorial Guidelines Updated on May 16, 2017 Print Rate It Share Share Tweet Pin Email Prep Time: 15 mins Total Time: 45 mins Servings: 4 This is a quick and easy supper. Using egg whites only will make the texture of the frittata more rubbery. Ingredients 2 tablespoons olive oil 1 large onion, halved and thinly sliced 1 (8 ounces) baking potato, peeled and thinly sliced ½ teaspoon dried rosemary, crumbled Coarse salt and ground pepper 5 large eggs 5 large egg whites ½ cup whole flat-leaf parsley leaves Directions In a medium (10-inch) nonstick broilerproof skillet, heat 1 tablespoon oil over medium heat. Add onion, potato, and rosemary; season with salt and pepper, and toss to combine. Cover skillet, and cook 10 minutes; uncover. Cook, tossing mixture occasionally, until onion and potato are tender, about 5 minutes. Meanwhile, in a medium bowl, whisk together eggs, egg whites, parsley leaves, 3/4 teaspoon salt, and 1/4 teaspoon pepper. Heat broiler with rack set 4 inches from heat. Add remaining tablespoon oil to vegetables in skillet. Pour egg mixture into skillet. Cook on stove, over low heat, lifting mixture a few times around the edges with a spatula to let egg flow underneath. Continue cooking until frittata is almost set in center, about 10 minutes. Place skillet under broiler; broil until frittata is set and top is lightly golden, about 3 minutes. Run a clean spatula around edges to loosen, then slide frittata out onto a serving plate, and cut into wedges. Cook's Notes Extra yolks: To store (for custards or egg washes), place unbroken yolks in water in a covered container and refrigerate, up to 2 days. If you have no use for them, you can buy unprocessed pure egg whites in the dairy section at the market. Rate it Print