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Potato Au Gratin

Creamy Sweet Potato Au Gratin for Cozy Holiday Feasts

This Creamy Sweet Potato Au Gratin is a delightful holiday casserole that combines creamy, cheesy goodness with sweet potatoes.
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Prep Time 15 minutes
Cook Time 55 minutes
Cooling Time 30 minutes
Total Time 1 hour 40 minutes
Servings: 8 servings
Course: Casserole
Cuisine: American
Calories: 350
Ingredients Equipment Method Nutrition Notes

Ingredients
  

For the Cream Sauce
  • 2 cups Heavy cream Can substitute with milk for a lighter option.
  • 4 cloves Garlic Use roasted garlic for a richer, sweeter flavor.
  • 2 teaspoons Fresh thyme Dried thyme works as a substitute.
  • 1 teaspoon Kosher salt Cut the amount by half if using table salt.
  • 1 teaspoon Fresh sage Dried sage can be used at about one-third the amount.
  • 1 teaspoon Black pepper Swap for white pepper if preferred.
  • 1/4 teaspoon Ground nutmeg Feel free to omit if not a fan.
For the Sweet Potatoes and Cheese
  • 2 lbs Sweet potatoes Regular potatoes can be used for a different flavor.
  • 3 oz Romano cheese Gruyere or cheddar are excellent alternatives.

Equipment

  • Casserole Dish
  • Mandolin slicer
  • Small pot

Method
 

Step-by-Step Instructions
  1. Preheat your oven to 400°F (200°C). Spray a 10x7 casserole dish with non-stick cooking spray.
  2. In a small pot over medium heat, combine heavy cream, minced garlic, fresh thyme, sage, kosher salt, black pepper, and ground nutmeg. Whisk and heat for 3-5 minutes without boiling.
  3. Peel and thinly slice the sweet potatoes to about ⅛ inch thickness using a mandolin slicer.
  4. Ladle a small amount of cream sauce into the bottom of the sprayed casserole dish. Spread evenly to keep the sweet potatoes moist.
  5. Layer the sweet potato slices over the cream sauce, overlapping slightly and alternating the direction of slices.
  6. Drizzle more cream sauce over the layer of sweet potatoes and sprinkle Romano cheese on top. Repeat this with remaining sweet potatoes, sauce, and cheese.
  7. Top with any leftover Romano cheese. Bake uncovered for 40 minutes, then cover with foil and bake for an additional 15 minutes.
  8. Let cool for about 30 minutes before serving to allow layers to set.

Nutrition

Serving: 1servingCalories: 350kcalCarbohydrates: 40gProtein: 8gFat: 18gSaturated Fat: 10gPolyunsaturated Fat: 1gMonounsaturated Fat: 6gCholesterol: 60mgSodium: 500mgPotassium: 600mgFiber: 4gSugar: 8gVitamin A: 15000IUVitamin C: 20mgCalcium: 300mgIron: 1.5mg

Notes

For a crispier top, switch to broiling for the last few minutes after baking.

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