Ingredients:

1 tablespoon unsalted butter -- plus additional for greasing dish

2 large onions -- halved lengthwise and thinly sliced crosswise

1 tablespoon ground cumin
1 teaspoon ground turmeric
pinch cayenne pepper

1 1/2 teaspoons kosher salt
freshly ground pepper -- to taste

2 cloves garlic -- peeled and minced

3 large baking potatoes -- peeled and cut into 1/16-inch slices

1 cup heavy cream

Directions:

1. Melt the butter in a large skillet over medium-low

2. Add the onions and cook, stirring frequently, until onions are
carmelized, about 30 minutes. Set aside. In a small bowl, stir
together the cumin, turmeric, cayenne, salt and pepper.Stir in the garlic.

3. Butter a 13-by-9-by 2-inch baking dish. Layer half of the potatoes in
dish, overlapping them slightly. Sprinkle with half of the spice mixture,
and with the onions. Layer the remaining potatoes over the onions.

4. Sprinkle with the remaining spice mixture, and pour the cream over the top.
Cover with aluminum foil and bake until the potatoes are tender, about 1
hour.

5. Let cool slightly, cut into rectangles and serve.
(The potatoes can be made ahead and reheated in a low oven, covered with aluminum foil.)