Scalloped Potatoes (French Pommes Boulangère)

In France these potatoes used to be prepared at home, then taken to the bakery (boulangère) to be cooked, hence their name.

3 Tbsp. butter
1 Tbsp. extra-virgin olive oil
4 onions, sliced
2 lb potatoes , thinly sliced
sea salt
black pepper, freshly cracked
fresh thyme sprigs, leaves picked
2 cups chicken or vegetable broth

Preheat the oven to 300°F (150°C/130°C fan, Gas Mark 2).

Melt half the butter with the olive oil in a saute pan, and gently fry the onions until soft and lightly golden, about 15 minutes. Spread half the onions in the bottom of a casserole . Lay a layer of sliced potatoes on top, season with salt and pepper, and scatter with thyme leaves. Build another layer of onions, then a final one of potatoes.  Pour the stock evenly over top.

Cover the pan with foil, and bake until all the liquid has been absorbed, 2-3 hours, removing the foil for the last hour if you like a crisp top.

Makes 6 servings.