Pin it
This irresistibly cheesy herb potato gratin is a crowd-pleasing side that brings cozy flavors to any meal. Layers of tender sweet potatoes and Yukon golds are kissed with fresh and dried herbs and bubbling Gruyère or sharp cheddar. Whether you serve it for a holiday or just with roast chicken on a weeknight, it always turns into a table favorite.
I still remember the first time I made this gratin for Thanksgiving dinner—every single person went back for seconds and even the kids were fighting for the crispy cheesy edges.
Ingredients
- Olive oil: Gives a subtle richness and helps keep the potatoes from sticking. Use extra virgin for deeper flavor.
- Sweet potatoes: Add a touch of sweetness and gorgeous color contrast for an eye-catching dish. Choose medium potatoes that feel firm and heavy.
- Yukon gold potatoes: Bring creaminess and a buttery texture. Small potatoes tend to have very thin skin, which is a bonus for flavor and presentation.
- Kosher salt: Pulls all the flavors together. I always use kosher salt for its clean taste and bigger crystals.
- Ground black pepper: Adds a warm kick and depth of flavor.
- Garlic powder: Gives reliable garlic flavor that blends smoothly with the cream and cheese.
- Dried thyme: Delivers earthy herbal notes that pair beautifully with potatoes. If using fresh, double the amount and mince finely.
- Ground sage: Provides a subtle woodsy aroma that makes the whole dish feel cozier.
- Dried parsley or fresh parsley: Both work. If using fresh, chop finely and add more for a pop of color.
- Dried rosemary or fresh rosemary: Essential for its piney aroma. Fresh rosemary will intensify the herb profile so chop it very fine.
- Gruyère or sharp white cheddar: Creates that perfect cheesy melt and nutty flavor. For best results, buy the cheese in a block and grate it just before baking.
- Yellow onion: Brings gentle sweetness and subtle savor to the whole dish. Sliced thinly so it melts right in.
- Whole milk or half-and-half: Gives that creamy texture you want in a gratin. Look for local or organic dairy when possible.
- Low-sodium chicken broth: Adds savoriness without overpowering the delicate flavors. Homemade or store-bought both work.
Step-by-Step Instructions
- Prepare the Pan:
- Brush the inside of a 10-inch cast iron skillet with olive oil making sure to cover all sides so your gratin slices release easily and get a little extra golden on the edge.
- Slice and Season Potatoes:
- Peel both the sweet potatoes and Yukon gold potatoes. Slice them very thin—about one eighth inch thick is ideal. A mandolin makes quick work but a sharp knife and patience will also work. Mix potato slices in a large bowl with salt pepper garlic powder thyme sage parsley rosemary most of the grated cheese and all of the onion. Toss gently with your hands so you do not break the slices.
- Layer in the Dish:
- Gather a small handful of the seasoned potato slices at a time and lean them upright in your prepared skillet or baking dish. Pack the slices snuggly in lines or swirls filling all the gaps. Sprinkle the reserved cheese evenly over the top for an extra crispy crust.
- Add Cream and Bake:
- Pour the milk and chicken broth evenly over the potato layers letting it seep down in between so every bite turns out creamy. Cover tightly with foil and seal well to trap steam.
- Bake Until Golden and Tender:
- Place the dish in the oven and bake at 375 degrees Fahrenheit for 50 minutes. Remove foil and return to the oven for 15 to 20 minutes more so the top gets crisp and golden. Check that a knife slides easily through all the potato layers. Let cool slightly before serving for best slicing.
Pin it
I have always loved the way Gruyère melts into pure silk in this recipe. Every time I make it I think back to Sunday dinners at my grandmother's house where creamy casseroles like this were always at the center of the table.
Storage Tips
Leftover potato gratin keeps well for up to four days in the refrigerator. Store it in an airtight container for maximum freshness. To reheat simply cover with foil and warm in a low oven until bubbling or microwave in short bursts to avoid drying it out. It actually tastes even better the next day as the flavors blend.
Ingredient Substitutions
Not a fan of sweet potatoes Simply swap them for more Yukon golds or try red potatoes for extra creaminess. For a vegetarian version use vegetable broth instead of chicken. If Gruyère is not available sharp white cheddar Havarti or even Monterey Jack can give you that ultra-melty result. For a different herb profile try adding chives or tarragon.
Serving Suggestions
This gratin pairs beautifully with roasted meats or poultry and brings a comforting touch to vegetarian spreads too. I love dishing it up with a crisp green salad and roast chicken or serving right alongside Thanksgiving turkey. For brunch it holds its own with a few fried eggs on top.
Pin it
I once tried skipping the step of grating fresh cheese and it was just not the same—the fresh-grated Gruyère absolutely makes the dish shine. If you have any fresh herbs left sprinkle them on just before serving for a burst of color and flavor.
Frequently Asked Questions
- → What potatoes work best for this gratin?
Sweet potatoes and Yukon Gold are ideal for their texture and flavor, creating creamy yet structured layers.
- → Can I use a different cheese?
Gruyère and sharp white cheddar are preferred, but you can experiment with fontina, mozzarella, or Swiss cheese for different flavors.
- → How do I get evenly thin potato slices?
A mandolin slicer is best for uniform, thin slices, ensuring even cooking and a professional look.
- → Is it possible to prepare this in advance?
You can assemble the gratin ahead and refrigerate, baking just before serving for optimal freshness and texture.
- → What herbs bring out the best flavor?
A blend of dried thyme, sage, rosemary, and parsley adds aromatic depth to the cheesy potato layers.