Peel the potatoes and cut them into chunks.
Add them to cold salted water and bring to the boil. Boil for about 10-15 minutes til tender, but not falling apart.
Drain the potatoes and shake them a little to rough up the edges. Let the potatoes steam for 5 minutes.
Preheat the oven to 400F / 220c (or as high as your oven will go).
Add two tablespoons of oil to your large cast iron skillet and place in the oven as it pre heats.
Place the parboiled potatoes in a large bowl and add in the ¼ cup of oil and all of the seasonings. Gently toss to combine, ensuring tthat the potatoes are well coated.
Once the oven is fully preheated, carefully remove the skillet from the oven and place in the potatoes (don't tip in the potatoes as the hot oil will splash.
Place in the oven and roast for 50 minutes or until the potatoes are crispy all over. Flip them halfway through cooking so that they get crispy all over.