- Preheat the oven to 200°C/Fan 180°C/Gas 6. Peel the potatoes and chop into large chunks then place in a large saucepan of cold salted water. Bring to the boil then simmer for about 6 minutes
- Meanwhile, add the goose fat (or duck fat or oil) to a large roasting tray and place in the oven to heat up
- Drain the potatoes in a colander and give them a gentle shake to fluff up the edges. Sprinkle over the semolina, shake again to coat evenly then leave to steam dry for 5 minutes. Leave the garlic cloves whole but crush lightly with the back of your hand or the flat side of a large knife
- Carefully add the potatoes to the hot tray along with the garlic and rosemary. Toss to coat in the fat and spread out in a single layer so they cook evenly
- Roast for 40-45 minutes, turning every 15 minutes, until crisp and golden brown. Season with sea salt and freshly ground black pepper to serve Perfect with Thorner's boned and rolled sirloin roast joint!