Instructions:

1. Prepare the mashed potatoes: Peel the potatoes and cut them into chunks. Boil the potatoes in salted water until fork-tender, then drain and mash them until smooth. You should have about 2 cups of mashed potatoes.
2. Preheat the skillet: Place a large skillet (preferably cast iron) over medium heat and preheat it while you prepare the dough.
3. Mix dry ingredients: In a large mixing bowl, combine the flour, baking powder, salt, garlic powder, onion powder, black pepper, chopped parsley (if using), and grated Parmesan cheese (if using). Stir until well combined.
4. Combine wet ingredients: In a separate bowl, whisk together the mashed potatoes, milk, and melted butter until smooth.
5. Form the dough: Pour the wet ingredients into the dry ingredients and stir until a soft dough forms. If the dough is too sticky, you can add a little more flour.
6. Shape the bread: Turn the dough out onto a lightly floured surface and shape it into a round loaf, about 1 inch thick.
7. Cook in the skillet: Grease the preheated skillet with butter or oil. Carefully transfer the shaped dough to the skillet. Cook the bread over medium heat for about 6-8 minutes on each side, or until golden brown and cooked through. You can cover the skillet with a lid or foil during cooking to ensure the bread cooks evenly.
8. Serve: Once the bread is cooked through and golden brown on both sides, remove it from the skillet and let it cool slightly on a wire rack. Slice and serve warm.