The recipe that follows addresses that conundrum by using both Yukon gold and sweet potatoes. It’s adapted from Third Thursday Community Potluck Cookbook, written by Nancy Vienneau, and makes 10 to 12 servings.
DOUBLE THE FLAVOR THANKSGIVING GRATIN
- 2 shallots, diced
- 1/4 cup butter, divided
- 2 cups heavy cream
- 2 tablespoons chopped parsley
- 1 tablespoon chopped chives
- 1 teaspoon kosher salt
- 1/2 teaspoon ground white pepper
- 1/8 teaspoon freshly grated nutmeg
- 1 1/2 lbs. Yukon gold potatoes
- 1 1/2 lbs. sweet potatoes
- 2 cups milk
- 1 1/2 cups (6 oz.) shredded Gruyere cheese
- 1/4 cup grated Parmesan cheese
- Preheat oven to 375 degrees F. Sauté shallots in 3 Tbsp. melted butter in a saucepan over medium heat for 2 minutes. Stir in cream, parsley, chives, salt, pepper and nutmeg, and cook for 2 minutes. Remove from heat, and cool 15 minutes.
- Meanwhile, peel and thinly slice all potatoes. Combine sliced potatoes and milk in a large, microwave-safe bowl. Cover with plastic wrap, and microwave on high for 5 minutes. Uncover and gently stir mixture. Re-cover and microwave 5 more minutes. Drain mixture, discarding milk.
- Layer one-third of Yukon gold potatoes in a well-greased (with butter) 9-inch by 13-inch baking dish. Top with one-third of sweet potatoes. Spoon one-third of cream mixture over potatoes, and sprinkle with 1/2 cup Gruyere cheese. Repeat layers twice, and top with Parmesan cheese. Cut remaining 1 Tbsp. butter into small pieces, and dot over top. Cover with foil.
- Bake at 375 degrees F for 30 minutes. Uncover, and bake 20 minutes or until browned. Let stand 10 minutes before serving.