Perfect Roast Potatoes

2 1/2 oz goose fat or duck fat or 5 tbsp olive oil
coarse sea salt
2 lbs even-size potatoes, peeled
8 fresh rosemary sprigs to garnish

Preheat the oven to 450 degrees. Put the fat or oil in a large roasting pan, sprinkle generously with sea salt, and place in the oven.

Meanwhile, cook the potatoes in a large pan of boiling water for 8-10 minutes, until parboiled. Drain well, and if the potatoes are large, cut them in half. Return the potatoes to the pan and shake vigorously to coarsen their outsides.

Arrange the potatoes in a single layer in the hot pan and roast for 45 minutes. If they look as if they are starting to char around the edges, lower the oven temperature to 400 degrees. Turn the potatoes over and roast for an additional 30 minutes, until crisp. Serve garnished with sprigs of rosemary.