2 pounds unpeeled baking (russet) potatoes, scrubbed
2 teaspoons table salt or 4 teaspoons kosher salt
3 tablespoons vegetable oil
3 onions, chopped
1 to 2 cloves garlic, mashed (optional)
6 large eggs
About 1/2 teaspoon ground white or black pepper
1/4 teaspoon ground turmeric
1 carrot, diced and cooked until tender
4 scallions, sliced
1/3 cup chopped fresh parsley or cilantro
1. Put the potatoes in a large pot and add cold water to cover by 1 inch and 1 teaspoon of the table salt or 2 teaspoons of the kosher salt. Bring to a low boil, reduce the heat to medium-low, and simmer, uncovered, until fork-tender, about 25 minutes. Drain. Peel the potatoes and, while still warm, run them through a food mill or ricer. Or, return the peeled potatoes to the warm cooking pot and mash with a potato masher, heavy whisk, or pastry blender over low heat, being careful not to over-mix.
2. Preheat the oven to 350°F.
3. In a large skillet, heat the oil over medium heat. Add the onions and sauté until lightly golden, about 15 minutes. If using, add the garlic and sauté for 1 minute.
4. Beat the eggs into the potatoes, one at a time. Stir in the remaining salt, the pepper, and turmeric. Add the onions, carrot, scallions, and parsley.
5. Generously oil a shallow 8-cup baking dish, such as 8-inch square and 7- by 11-inches, then heat in the oven until hot, about 3 minutes. Carefully spoon the potato mixture into the baking dish. Bake until golden and set, about 50 minutes. Serve warm or at room temperature.
DAIRY POTATO CASSEROLE: Reduce the eggs to 2 and add 1 cup (8 ounces) cream cheese or 1 cup sour cream, or 3/4 cup (6 ounces) cream cheese and 1/2 cup (2 ounces) grated Parmesan cheese. Bake the casserole for about 40 minutes, sprinkle with 1/2 cup grated Parmesan or shredded Cheddar cheese, and continue baking for about 10 minutes.