Sweet Potato Gratin with onions and sage


by: Carol

Although my eating habits have improved over the years, I still have a great fondness for creamy gratins, which I make on special occasions. This tender sweet potato gratin is definitely a treat. Don’t try to make it with milk-it won’t work. For an accompaniment, look to some authoritative greens, such as a big plate of mustard greens, broccoli rabe, or seared radicchio, or an equally pungent salad of bitter greens. I like something sweet here as well, such as a cranberry relish, apple-quince sauce, or quince compote. For wine, why not go with a creamy rich Chardonnay, such as Martinelli from the Russian River? Cream and butter always go with Chardonnay.


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serves: 6

2 teaspoons oil, plus a little for the dish

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

2 tablespoons chopped sage (or 2 teaspoons dried)

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

sea salt and freshly ground pepper

1 large handful of parsley leaves (chopped with 1 plump garlic clove)

3/4 cup grated Gruyere or smoked mozzarella cheese

freshly grated Parmesan cheese

1 cup cream or half-and-half, warmed

Nutrition Facts
Sweet Potato Gratin with onions and sage

Servings Per Recipe: 6

Amount per Serving

Calories: 346

  • Total Fat: 11.7 g
  •     Saturated Fat: 6.2 g
  •     Trans Fat: 0 g
  • Cholesterol: 33.1 mg
  • Sodium: 202.4 mg
  • Total Carbs: 51.3 g
  •     Dietary Fiber: 7.6 g
  •     Sugars: 11 g
  • Protein: 10.1 g

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1.  Preheat the oven to 350°F. Lightly oil a 2-quart gratin dish and put a moderately large pot of water on to boil.

2.  Put 2 teaspoons 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.

3.  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.

4.  Scoop a third of the potatoes into the prepared dish and even them out. Season with salt and pepper, add half the Gruyere, and grate over a little Parmesan. Repeat, making two more layers and covering the last with a dusting of the 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 utterly soft and the gratin has browned, another 25 minutes or so. Let the gratin stand a few minutes before serving. If you’re not ready to eat, it can wait in the turned-off oven for another half hour.

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