Sometimes, the side dishes are the best part of the meal. That’s where this comes from. I had a meal restaurant meal that was generally unremarkable, but for a dish ordered for the table as something of an afterthought. It inspired me. That dish was a slightly overwrought, oddly-shaped plate with a small swipe of béchamel sauce topped with roasted sweet potatoes and a sprinkling of country ham and some gruyere, run under a broiler. But it got the wheels turning in my head though. A creamy sauce with rich roasted potatoes and salty country ham and nutty gruyere works together beautifully. I knew it would make a fantastic gratin, with plenty of each ingredient perfectly balanced.
Give this a try for Thanksgiving, it’s a switch from the cinnamon and brown sugar versions we are used to in the best possible way. And it can be made a day ahead to cut down on turkey day chaos. Every time I have served this, it’s gotten absolute raves. It’s also great beside a roasted chicken or pork loin, and frankly would make a great main dish. I like to use center cut biscuit sliced of country ham which are easy to find.
Sweet Potato and Country Ham Gratin
4 medium sweet potatoes
¼ cup olive oil
Salt and pepper
About 6 ounces country ham, to make 1 cup finely diced ham
1 leek, white and light green part
4 Tablespoons unsalted butter
2 Tablespoons flour
2 cups whole milk
1 ½ cups grated gruyere cheese
Preheat the oven to 425 degrees. Line a rimmed baking sheet with foil sprayed with cooking spray.
Peel the sweet potatoes and cut into chunks about ½ inch square as evenly sized as can be. Place the potato chunks in a ziptop bag and pour over the olive oil. Sprinkle liberally with salt and pepper, then toss around to coat all the potato pieces with oil. Spread in an even layer on the prepared baking sheet and roast for 20 minutes. Finely dice the country ham. Remove the pan from the oven and gently turn the potato pieces over with a spatula. Sprinkle the diced ham over the top of the potatoes and return the pan to the oven for a further 15 – 20 minutes, until the potatoes are soft and the edges are brown and crispy. Set aside to cool to room temperature.
While the potatoes are roasting, cut the white and lightest green part of the leek in half, then into quarters and thinly slice. Place in a colander, rinse well and shake to remove as much water as possible. Melt 2 tablespoons of the butter in a deep skillet and sauté the leeks until they are soft and glassy. Try not to let them brown. Add the remaining two tablespoons butter, and when it is melted, sprinkle over the flour. Stir to coat the leeks in the flour and cook for a few minutes. Stir in the milk and bring to a nice bubble. Stir frequently until the sauce is thickened. Season with salt and pepper to taste. Let cool for 10 minutes, then gently stir in the roasted potatoes, making sure they are well coated in sauce
Spread the potatoes in a baking dish, then sprinkle over the gruyere. At this point, the dish can be covered and refrigerated overnight. When ready to bake, preheat the oven to 350 degrees. Cook the gratin for 20 – 30 minutes, until heated through and bubbly and the cheese is melted.