Heat oven to 180C/160C fan/gas 4. Peel the
potatoes and cut them into cubes. Put the
garlic, thyme and oil in a large roasting tin,
and put it in the oven for 5 mins.
Tip the potatoes into the roasting tin,
quickly turn them to coat in the oil, then
spread them out in a single layer. Season well
and roast for 1–11/2 hrs, turning occasionally
during cooking, until golden and crispy.