If you’re craving a comforting side dish that feels like a warm hug on a plate, you have to try this Simple Sweet Potato Gratin with Cheesy Gruyère and Thyme Recipe. It’s a beautiful blend of thinly sliced sweet potatoes layered with rich, nutty Gruyère cheese and fragrant fresh thyme. What’s truly special here is how this gratin achieves such creamy indulgence without heavy cream or milk, keeping it lighter but no less decadent. It’s a golden, bubbly masterpiece that brings a lovely balance of buttery, cheesy, and herbaceous flavors, perfect for any occasion where you want to impress with ease.
Ingredients You’ll Need
This recipe shines because it uses straightforward, wholesome ingredients. Each one plays a critical role in building layers of flavor and texture, from the natural sweetness of the potatoes to the sharp, melty cheeses and the fragrant thyme that lifts it all.
- Sweet potatoes (5 medium, about 2 lbs): The star of the dish, providing natural sweetness and a tender texture when baked.
- Butter (2 tablespoons, melted): Adds richness and helps the potatoes brown beautifully during baking.
- Gruyère cheese (1 cup, grated): Brings a nutty, creamy depth that melts into the potatoes for perfect cheesy goodness.
- Parmesan cheese (⅔ cup, grated): Adds sharpness and a wonderful golden crust when baked.
- Fresh thyme (1.5 tablespoons plus extra for serving): Infuses the gratin with a delicate herbaceous aroma that brightens each bite.
- Kosher salt (1 teaspoon): Enhances every flavor, making the dish well-seasoned and balanced.
- Ground black pepper (½ teaspoon): Adds a mild kick and rounds out the seasoning.
- Garlic powder (½ teaspoon): Imparts a subtle savory note that complements the cheese and thyme beautifully.
How to Make Simple Sweet Potato Gratin with Cheesy Gruyère and Thyme Recipe
Step 1: Prepare the Sweet Potatoes and Baking Dish
Start by preheating your oven to 425 °F and generously butter or oil a 3-quart gratin dish or a 9×13 baking pan to prevent sticking. Give those sweet potatoes a good wash and dry to remove any dirt. Peel them carefully with a vegetable peeler, then slice each potato paper-thin — about ⅛ inch thick — using a mandolin slicer if you have one. These thin slices are critical for that melt-in-your-mouth texture.
Step 2: Toss the Potatoes with Butter and Seasonings
Place your thinly sliced sweet potatoes into a large mixing bowl and pour in the melted butter, sprinkle over the fresh thyme, kosher salt, black pepper, and garlic powder. Toss everything gently but thoroughly, ensuring each delicate slice is coated with this flavorful mixture. This step creates a savory base that elevates the sweetness and blends beautifully with the cheeses.
Step 3: Build the Layers of Delight
Now the fun part: layering! Lay down about a third of your potato slices in the bottom of your prepared dish, overlapping slightly like shingles to create a snug base. Sprinkle one-third of the combined Gruyère and Parmesan cheese evenly over this layer. Press the potatoes lightly to settle them in, then repeat this layering process two more times, finishing with the remaining cheeses on top. This layering ensures every forkful is a perfect balance of potatoes and cheesy goodness.
Step 4: Bake Covered, Then Uncover for Golden Finish
Cover your gratin tightly with aluminum foil. To avoid the foil sticking to your glorious cheesy top, lightly spray the foil with olive oil on the side that will touch the food. Bake it on the middle oven rack for 30 minutes to soften the potatoes and meld the flavors. After this initial bake, remove the foil and move the dish to the top oven rack. Bake for another 10–15 minutes until the gratin is beautifully golden, bubbling with melted cheese that promises pure deliciousness.
Step 5: Rest and Serve
Once your gratin emerges from the oven with a gorgeous golden crust, grant it a few minutes to cool and set before serving. This little moment lets everything settle so you get those neat, creamy slices everyone will rave about. Now it’s ready to enjoy!
How to Serve Simple Sweet Potato Gratin with Cheesy Gruyère and Thyme Recipe
Garnishes
To elevate the presentation and flavor, sprinkle fresh thyme leaves on top right before serving. It adds a pop of green and a lovely fresh note that brightens every bite. If you love a little heat, a pinch of smoked paprika or some crushed red pepper flakes can add a surprising but delightful kick.
Side Dishes
This gratin is a lovely companion to roasted meats like chicken, pork, or even a standing rib roast. It pairs wonderfully with crisp green salads or sautéed greens like spinach and kale, which cut through the richness with fresh, earthy contrast. For a vegetarian meal, serve alongside a vibrant vegetable ratatouille or a crunchy kale salad tossed with lemon vinaigrette.
Creative Ways to Present
Looking to make this dish the star of your table? Try baking the gratin in individual ramekins for charming, personalized servings. You can also add extra layers with caramelized onions or a sprinkle of crispy breadcrumbs on top for added texture. Serve it as a decadent brunch dish alongside poached eggs and fresh herbs for a special weekend treat.
Make Ahead and Storage
Storing Leftovers
If you have any leftovers from your Simple Sweet Potato Gratin with Cheesy Gruyère and Thyme Recipe, store them in an airtight container in the refrigerator for up to four days. The flavors actually deepen over time, making your next meal just as delicious.
Freezing
You can freeze this gratin by placing it in a freezer-safe container once cooled. Keep it frozen for up to two months. When ready to enjoy, thaw it overnight in the fridge for best texture and flavor.
Reheating
Reheat leftovers gently in the microwave or oven until warm and bubbly. If using the oven, cover the gratin with foil and heat at 350 °F for about 20 minutes. This helps preserve the creamy texture and prevents the cheese from drying out.
FAQs
Can I use other types of potatoes for this gratin?
Absolutely! While the Simple Sweet Potato Gratin with Cheesy Gruyère and Thyme Recipe shines with sweet potatoes, you can swap in Yukon gold or even russet potatoes depending on your preference. Just note that cooking times might vary slightly.
Is there a way to make this dish vegan or dairy-free?
To make this vegan, try substituting the Gruyère and Parmesan with plant-based cheese alternatives that melt well and have a strong flavor. Use olive oil or vegan butter instead of regular butter. Fresh thyme will still give that wonderful herb flavor.
How thin should the sweet potato slices be?
Thin slices about ⅛ inch thick are ideal. This ensures the potatoes cook evenly, become tender without drying out, and meld perfectly with the cheese layers to achieve that luscious gratin texture.
Can I prepare the gratin ahead of time before baking?
Yes! You can assemble the gratin up to a day in advance and keep it covered in the refrigerator until you’re ready to bake. Just add a few extra minutes to the baking time if baking straight from cold.
Why do you cover the gratin with foil during part of the baking?
Covering the gratin helps the potatoes steam and cook through gently without over-browning the top too soon. Removing the foil at the end lets the cheese brown and bubble to that irresistible golden finish.
Final Thoughts
I truly hope you give this Simple Sweet Potato Gratin with Cheesy Gruyère and Thyme Recipe a try because it’s one of those dishes that feels like a cozy celebration every time you make it. The combination of sweet potatoes with melty Gruyère and fresh thyme is utterly irresistible. It’s comfort food that’s elegant enough for special dinners but simple enough for weeknights. Enjoy every golden, cheesy bite!
Print
Simple Sweet Potato Gratin with Cheesy Gruyère and Thyme Recipe
- Prep Time: 20 minutes
- Cook Time: 45 minutes
- Total Time: 1 hour 5 minutes
- Yield: 6 servings
- Category: Side Dish
- Method: Baking
- Cuisine: American
- Diet: Vegetarian
Description
This Simple Sweet Potato Gratin is a delicious, cheesy dish made with thinly sliced sweet potatoes layered with gruyere and parmesan cheese, fresh thyme, and seasoned with garlic powder, salt, and pepper. Baked until golden and bubbly, this gratin is rich and buttery without the use of milk or cream, making it a lighter yet decadent twist on a classic comfort food side dish.
Ingredients
Sweet Potatoes and Seasoning
- 5 medium sweet potatoes – about 2 lbs
- 2 tablespoons butter – melted
- 1.5 tablespoons fresh thyme (plus more for serving)
- 1 teaspoon kosher salt
- ½ teaspoon ground black pepper
- ½ teaspoon garlic powder
Cheeses
- 1 cup grated gruyere cheese
- ⅔ cup grated parmesan cheese
Instructions
- Prepare the Baking Dish: Preheat your oven to 425°F. Lightly grease a 3-quart gratin dish or a 9×13 baking dish with butter or oil to prevent sticking.
- Slice the Sweet Potatoes: Wash and dry the sweet potatoes thoroughly. Peel them using a vegetable peeler and discard the peels. Using a mandolin slicer, slice the sweet potatoes into thin, uniform slices about ⅛ inch thick for even cooking.
- Toss Potatoes with Seasoning: Place the sliced sweet potatoes in a large mixing bowl. Pour the melted butter over them, then add fresh thyme, kosher salt, ground black pepper, and garlic powder. Toss well to coat all the slices evenly with the butter and seasonings.
- Layer the Gratin: Start by layering one-third of the sweet potato slices evenly at the bottom of the prepared baking dish, overlapping slightly. Sprinkle one-third of the combined cheeses (gruyere and parmesan mixed together) over the potatoes. Press down gently to snug the layers. Repeat this layering two more times, finishing with the cheese on top.
- Cover and Bake: Cover the gratin with foil, spraying the foil with olive oil spray on the side facing the potatoes to prevent sticking. Place the dish on the middle rack of the oven and bake for 30 minutes.
- Bake Uncovered to Brown: Remove the foil and move the gratin to the top rack in the oven. Continue baking uncovered for an additional 10-15 minutes, until the top is golden brown and bubbly.
- Cool and Serve: Take the gratin out of the oven and allow it to cool for a few minutes before serving. Garnish with extra fresh thyme if desired for a fragrant finish.
Notes
- You can use other potatoes such as Yukon Gold or russet potatoes if preferred for this recipe.
- Store any leftovers in an airtight container in the refrigerator for up to 4 days.
- Reheat leftovers in the microwave until fully warmed through and the cheese is melted again.
- For make-ahead instructions, the dish can be assembled and refrigerated before baking.
