This week's meatless recipe is a decadent dish from "Vegetarian Suppers From Deborah Madison's Kitchen." If you can't indulge this week, when can you?

Sweet-Potato Gratin With Onions and Sage

Yield: Serves 4

Ingredients:

2 teaspoons oil plus a little for cooking dish

1 large onion, chopped into 1/2 -inch dice

2 tablespoons chopped fresh sage or 2 teaspoons dried

3 medium sweet potatoes (about 1 1/2 pounds), thinly sliced

1 large handful of fresh parsley leaves, chopped

1 plump garlic clove, finely chopped

sea salt and freshly ground black pepper to taste

3/4 cup grated Gruyere or smoked mozzarella cheese (divided use)

1 to 2 tablespoons grated parmesan cheese (divided use)

1 cup cream or half-and-half, warmed (milk won't work)

Preheat oven to 350 degrees. Lightly oil a 2-quart gratin dish and put a moderately large pot of water on to boil. Put 2 teaspoons of oil in a skillet over medium heat and add the onion and sage. Cook, giving them an occasional stir, until soft and golden, about 12 minutes.

Meanwhile peel the sweet potatoes, then slice them as thinly as you can manage. Salt the water, then drop them in. Allow the water to return to a boil, which may take a few minutes. Boil for a minute or until the potatoes are partly tender when pierced with a knife, then drain. Toss them with the onions, chopped parsley and garlic.

Scoop a third of the potato mixture into the prepared gratin dish and even the potatoes out. Season with salt and pepper. Add half the Gruyere and grate a little parmesan over the mixture. Repeat making one or two more layers, covering the last with a dusting of parmesan.

Pour the warm cream over all. Cover with foil and bake in the center of the oven for 25 minutes. Remove the foil and continue baking until the potatoes are soft and the gratin has browned, another 25 minutes of so. Let the gratin stand a few minutes before serving.

If you have a favorite vegan or vegetarian dish, email us with the recipe, source (if it's not your own) and photo (if you have one), and we may feature it in future posts. If we choose your recipe, we'll also send you a book related to vegetarian or green eating.

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