Preheat the oven to 450°F.
Peel and cut the potatoes into 1½-inch cubes.
3-4 pounds russet potatoes
Add the potatoes to a large pot with the salt and baking soda and add cold water to cover the potatoes.
1 tablespoon salt, ½ teaspoon baking soda
Place the pot of potatoes on the stove, cover and bring to a rapid boil over high heat. Cook the potatoes for 10 minutes or until fork tender. Remove the lid once the water is boiling and if necessary, reduce the heat to avoid the water boiling over.
Drain the potatoes and return the potatoes to the hot pot without the lid, but do not put them back on a hot burner. Allow the potatoes to steam off the excess moisture for a few minutes. Then put the lid on and shake up the potatoes hard. (Roughing up the parboiled potatoes will give them more crunch once they are roasted.)
Add the duck fat to a large deep cast iron pan and place it into the oven for about 5 minutes, or until it is just starting to smoke. Once the duck fat is melted, add the potatoes to the skillet. (It is best for them to cook in a single layer, using 2 skillets if necessary.)
½ cup duck fat
Transfer the skillet back into the oven and allow the potatoes to cook undisturbed for 30 minutes. Then turn the potatoes over and allow them to cook for an additional 15 minutes. Turn them again, and allow them to cook for another 15 minutes or until golden and crunchy.
When you remove the potatoes from the oven, sprinkle them with seasoning salt, pepper, garlic powder, and onion salt. Serve them hot and fresh out of the oven.
½ teaspoon seasoning salt, ¼ teaspoon ground black pepper, ¼ teaspoon garlic powder, ¼ teaspoon onion salt, fresh oregano, fresh parsley, fresh sage, fresh rosemary, parmesan cheese