6 tablespoons sunflower oil, for roasting
1 large whole garlic bulb, halved widthways
Sea salt and black pepper, to taste
2 1/2 pounds (1.2kg) floury potatoes (such as Maris Piper or Russet), skin on and cut into 1 1/2–inch (4cm) chunks
Stir-Fried Scallions & Soy Dressing
2 tablespoons sunflower oil
8 scallions, chopped into 1-inch (3cm) chunks
8 garlic cloves, peeled and thinly sliced
4 1/2 inches (12cm) ginger (about 60 grams), peeled and cut into long, thin matchsticks
1/4 cup rice vinegar or white wine vinegar
1/4 cup light soy sauce
Heat the oven to 425°F. Pour the oil into a very large, heavy-bottomed roasting tray with the garlic bulb halves and a generous sprinkle of salt. Place the roasting tray in the oven to heat.
Put the potatoes into a large pan and cover with cold water. Add 1 tablespoon of salt and bring to the boil, then reduce the heat and simmer for 5 minutes. Drain the potatoes, then return them to the pan to steam for 2 minutes. As the potatoes are steaming, shake the pan to rough up their edges for maximum crispiness.
Remove the hot roasting tray from the oven and carefully spoon the potatoes into the pan in a single layer, being careful not to overcrowd the tray. Toss the potatoes in the hot oil until they are fully coated, then season generously with salt and pepper. Roast for about 45 minutes, until golden and crispy, turning the potatoes over halfway to ensure even roasting. If the garlic bulbs get to a deep golden brown before the potatoes, remove the garlic from the pan and set aside until the potatoes are done.
In the last 10 minutes of the cooking time, prepare the stir-fried scallions and the soy dressing: Heat the oil in a frying pan over a medium heat and add the spring onions, garlic and ginger. Cook for 2 to 3 minutes until fragrant and just beginning to soften, then remove from the heat. To make the dressing, mix the vinegar and soy sauce in a small bowl and set aside.
Once golden, toss the potatoes with the spring onion, garlic and ginger, then drizzle with the vinegar and soy dressing. Serve immediately.