Recipes Ingredients Meat & Poultry Pork Recipes Baked Stuffed Sweet Onions 3.0 (2) Add your rating & review 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 June 12, 2017 Print Rate It Share Share Tweet Pin Email Photo: Formula Z/S Servings: 4 The mildness of sweet onions make them ideal for this delicately hearty side. Ingredients 4 medium sweet onions ½ teaspoon coarse salt, plus more for cooking water 2 tablespoons extra-virgin olive oil 6 ounces (about 9) cremini mushrooms, trimmed and cut into ½-inch pieces 4 ounces Virginia ham, cut into ¼-inch pieces ¼ teaspoon freshly ground pepper 3 tablespoons Madeira wine ¼ cup chopped fresh flat-leaf parsley 1 cup grated (about 2 ounces) Gruyere cheese Directions Preheat oven to 400 degrees. Peel onions; slice 1/2 inch from top of each, and discard. Slice just enough from the root end so that onions stand upright. Using a melon baller, hollow out the insides, leaving a 1/3- to 1/2-inch-thick shell. Set aside. Finely chop removed parts, and set 1 cup chopped onion aside. Discard remaining onion or reserve for another use. Bring a large pot of water to a boil; add salt. Gently submerge onion shells, and boil 5 minutes. Remove with a slotted spoon; transfer to a wire rack to dry. Make the stuffing: In a large saute pan, heat 1 tablespoon oil over medium heat. Add reserved chopped onions, and cook until translucent, about 8 minutes. Add mushrooms and ham, and season with salt and pepper; cook until mixture is browned, about 5 minutes. Add Madeira; deglaze pan, stirring with a wooden spoon to loosen any brown bits on bottom. Remove from heat, and transfer to a small mixing bowl; let cool slightly, 2 to 3 minutes. Add parsley and Gruyere cheese, and stir to combine. Fill boiled onion shells with stuffing. Place in a small roasting pan; drizzle with remaining tablespoon oil. Cover with aluminum foil. Bake until tender, about 50 minutes; remove foil after 40 minutes to allow stuffing to brown. Rate it Print