New Tradition! – Sweet Potato Gratin

When it comes to Thanksgiving meal items, there is usually a bit of a struggle in our home. I like to branch out and try new dishes. Others in the family prefer the traditional items. (I can’t write or think about the word “tradition” at this time of year without hearing Eric break into his best Tevye impression from Fiddler on the Roof, talking & singing about “Tradition!” Unless, of course, Gilbert beats him to it!)

To deal with this yearly debate, we prepare mainly the tried and true dishes with 2 (maybe 3) new ones. We typically try the new suggestions ahead of the feast to ensure they are an asset to the meal. Today’s recipe got a resounding, “Yes!” from all the family members at its trial debut.

A mix of purple, orange, and white sweet potatoes are sliced and layered with a creamy cheese sauce. Parmesan is the cheese element of the sauce. Its tangy, nutty, and sharp flavor gives the sauce a complex flavor profile with a strong umami taste. Shredded Gruyère cheese sprinkled between the layers of potatoes and sauce add to the rich and creamy nature of the overall dish. Garlic, thyme, and sage provide earthy tones to the cheese sauce. A warming & seasonal element is incorporated into the gratin with the addition of cinnamon & nutmeg to the sauce.

This combination of sweet potatoes and cheese sauce is a wonderful new addition to our Thanksgiving feast!

Sweet Potato Gratin

Sweet Potato Gratin (adapted from delish.com) Total Time Required: 2 hours, Prep Time: 30 minutes, Makes: 12 servings

Ingredients:

  • 3 tablespoons unsalted butter, softened, divided
  • 4 teaspoons cloves garlic, chopped
  • 2 tablespoons chopped fresh thyme leaves, plus more for serving
  • 1 tablespoon chopped fresh sage leaves
  • kosher salt & freshly ground black pepper
  • 1 cup heavy cream
  • 3/4 cup whole milk
  • 1/4 teaspoon ground cinnamon
  • 1/4 teaspoon ground nutmeg
  • 2 large eggs
  • 3/4 cup grated Parmesan (about 2 ounces), divided
  • 2 pounds sweet potatoes (mix of purple, orange, and white), peeled and sliced 1/8″ thick
  • 2-2/3 cup shredded Gruyère cheese (about 8 1/2 ounces), divided

Directions:

Preheat the oven to 375°F. Butter a 2-quart casserole or gratin dish with 1 tablespoon of the butter. In a small saucepan over medium heat, melt the remaining 2 tablespoons of butter. When the butter stops foaming, add the garlic and cook, stirring, until it is fragrant, about 30 seconds.

Add the garlic to the foaming butter.

Add the thyme, sage, and 1/2 teaspoon salt and cook, stirring occasionally, until all is heated through, about 30 seconds.

Add the thyme, sage, and salt.

Add the cream, milk, cinnamon, and nutmeg. Bring to a simmer without letting it come to a boil, and cook, stirring occasionally, until slightly thickened, about 5 minutes. Remove the cream mixture from the heat.

Add the cream, milk, cinnamon, and nutmeg.

In a medium bowl, beat the eggs. Transfer 1 cup of the cream mixture to a liquid measuring cup. Whisking constantly, slowly stream the cream mixture into the eggs a few tablespoons at a time until all the cream is incorporated into the eggs. Add the cream & egg mixture back into the saucepan with the remaining cream mixture and whisk until combined.

Combine the eggs with some of the cream sauce then slowly add it back into the pot.

Whisk in 1/2 cup of Parmesan.

Whisk in some of the Parmesan cheese.

Line the bottom of the buttered casserole dish with a layer of potatoes, slightly overlapping the slices. Season the slices with a pinch of salt.

Start with the purple sweet potato slices.

Top with 2/3 cup of the Gruyère and 2/3 cup of the cream mixture.

Top the first layer with some of the Gruyère and cheese sauce.

Repeat 3 times, ending with the cream mixture.

Repeat the layers with the orange sweet potatoes . . .

. . . then the white sweet potatoes.

Top the final layer with the remaining 1/4 cup of Parmesan.

Top the layers with the rest of the Parmesan cheese.

Butter a piece of foil and tightly cover the dish. Bake the gratin for 30 minutes, uncover, and continue to bake until the sides are bubbling and golden brown, about 30 minutes more.

Bake the gratin for 30 minutes covered, then 30 minutes uncovered.

Top the gratin with thyme before serving.

Top with additional thyme and serve.

This “new” dish is now part of our Thanksgiving tradition!  ~Linda

Sweet Potato Gratin (adapted from delish.com) Total Time Required: 2 hours, Prep Time: 30 minutes, Makes: 12 servings

Ingredients:

  • 3 tablespoons unsalted butter, softened, divided
  • 4 teaspoons cloves garlic, chopped
  • 2 tablespoons chopped fresh thyme leaves, plus more for serving
  • 1 tablespoon chopped fresh sage leaves
  • kosher salt & freshly ground black pepper
  • 1 cup heavy cream
  • 3/4 cup whole milk
  • 1/4 teaspoon ground cinnamon
  • 1/4 teaspoon ground nutmeg
  • 2 large eggs
  • 3/4 cup grated Parmesan (about 2 ounces), divided
  • 2 pounds sweet potatoes (mix of purple, orange, and white), peeled and sliced 1/8″ thick
  • 2-2/3 cup shredded Gruyère cheese (about 8 1/2 ounces), divided

Directions:

Preheat the oven to 375°F. Butter a 2-quart casserole or gratin dish with 1 tablespoon of the butter. In a small saucepan over medium heat, melt the remaining 2 tablespoons of butter. When the butter stops foaming, add the garlic and cook, stirring, until it is fragrant, about 30 seconds. Add the thyme, sage, and 1/2 teaspoon salt and cook, stirring occasionally, until all is heated through, about 30 seconds. Add the cream, milk, cinnamon, and nutmeg. Bring to a simmer without letting it come to a boil, and cook, stirring occasionally, until slightly thickened, about 5 minutes. Remove the cream mixture from the heat.

In a medium bowl, beat the eggs. Transfer 1 cup of the cream mixture to a liquid measuring cup. Whisking constantly, slowly stream the cream mixture into the eggs a few tablespoons at a time until all the cream is incorporated into the eggs. Add the cream & egg mixture back into the saucepan with the remaining cream mixture and whisk until combined. Whisk in 1/2 cup of Parmesan.

Line the bottom of the buttered casserole dish with a layer of potatoes, slightly overlapping the slices. Season the slices with a pinch of salt. Top with 2/3 cup of the Gruyère and 2/3 cup of the cream mixture. Repeat 3 times, ending with the cream mixture. Top the final layer with the remaining 1/4 cup of Parmesan.

Butter a piece of foil and tightly cover the dish. Bake the gratin for 30 minutes, uncover, and continue to bake until the sides are bubbling and golden brown, about 30 minutes more. Top the gratin with thyme before serving.

Leave a Reply