Sweet Potato Gratin in Herbed Cream

Sweet Potato Gratin In Herbed Cream

Yields: 4 to 6 servings
Preparation time: 20 minutes
Cooking time: about 2 hours, divided
Cooling time: at least 30 minutes

Time to come up with a new twist for sweet potatoes without just mashing them up, throwing some marshmallows on it and calling it a day.

Go to the store and get this stuff.

For the cream:
1 tablespoon butter
1 small yellow onion, diced (about 1/2 cup)
fresh herbs like thyme, oregano, parsley. About 2 tbsp.
1/4 cup dry white wine
1 pint heavy cream
1/2 to 1 cup chicken stock. I either make my own or use Swanson's.

For the gratin:
3 1/2 pounds (about 5 medium) sweet potatoes
1 tablespoon butter
Salt and freshly ground black pepper
1 cup grated Parmigiano Reggiano
1 cup grated Gruyere cheese

To make the herbed cream: Melt the butter in a medium saucepot over medium heat. Add the onions and sweat them, stirring occasionally, until onions are translucent, about 5 minutes.
Add the herbs and white wine and increase the heat to medium-high. Reduce wine until almost dry. Make sure you pour yourself a glass.
Add cream and return to a simmer, reducing heat to medium-low once it starts simmering, until liquid is reduced to 11/2 cups, about 1 hour, or another glass of wine.
While cream mixture is reducing, peel sweet potatoes. Slice into 1/8-inch-thick rounds on a mandolin. Set aside. Makes it prettier and the gratin will cook evenly.
Preheat oven to 375 degrees.
Transfer the mixture to a blender and carefully blend, starting on low speed and increasing to high speed until smooth, about 1 minute. Pass through a fine strainer into a large bowl or glass measuring cup, discarding any solids. Stir in 1/2 cup of the chicken stock and set aside.
To make the gratin: Rub butter ( Don't be shy) to coat the bottom and sides of a 3-inch deep 8-inch-square or 9 x 13-inch baking dish. Spread 1/2 cup of the cream mixture evenly over the bottom of the pan.
Arrange slices of sweet potato in slightly overlapping rows to cover the bottom of the dish. Season with salt and pepper. Sprinkle a bit of both cheeses and then about 1/2 cup of the cream mixture evenly over the layer.
Repeat this process until the dish is almost full or all the potatoes are used. On the top layer, spread the remaining cream mixture. Sprinkle evenly with remaining cheese. Cover tightly with aluminum foil. Kinda like making a lasagna, but not.
Bake until the sweet potatoes are soft when poked with a fork, 40 to 45 minutes. Remove the foil. If the gratin seems too dry, drizzle with the remaining 1/2 cup stock. Return the gratin to the oven and bake until cheese is browned, 15 to 20 minutes more.
Let gratin cool on a rack at room temperature until it sets, at least 30 minutes. Patience, Grasshopper! Cover and reheat if necessary before serving.

I like this because I can make it very early on Thanksgiving morning and it is done before I tie up the oven with other stuff. Also great to travel with! Not on a plane, though.