Kentang Daun Renyah

Bahan-bahan (10 porsi)

• 9 lbs . (4kg) potatoes (peeled, yukon gold or russet)
• 12 oz . (350g) unsalted butter (melted or 11 oz. (311g) duck fat)
• 3 teaspoons Maldon sea salt flakes (preferred or salt)
• 1 teaspoon freshly ground black pepper
• 4 teaspoons chopped rosemary (or oregano)