Description
A creamy, cheese-filled Wisconsin take on classic French potatoes au gratin. Thinly sliced potatoes are cooked in one pan with broth, mascarpone, and garlic, then baked with cream and melty cheese until tender and bubbly. Perfect for holidays, Sunday dinners, and cozy family meals.
Ingredients
- 1 1/2 pounds yellow potatoes, such as Yukon Gold, sliced 1/8-inch thick
- 2 cups vegetable broth
- 2-3 garlic cloves, grated
- 1 tablespoon Chinese mustard
- 4 ounces mascarpone cheese
- 1/4 cup freshly grated Parmesan cheese
- 1 teaspoon salt
- 1/2 teaspoon ground white pepper
- 1 cup heavy cream, gently warmed
- 4-8 ounces shredded marbled jack cheese
Instructions
- Preheat the oven. Preheat oven to 375°F.
- Slice the potatoes. Slice the yellow potatoes 1/8-inch thick using a knife, mandoline, or food processor slicing blade. Leave the skins on for a rustic texture, or peel if preferred. Do not rinse the slices, as the natural starch helps thicken the sauce.
- Make the base. In a 3.5-quart enameled cast iron pan, combine the vegetable broth, grated garlic, Chinese mustard, mascarpone cheese, salt, and white pepper. Cook over medium heat, stirring gently, until the mascarpone is fully melted and the mixture is smooth.
- Add the potatoes. Add the sliced potatoes a handful at a time, gently stirring between additions to coat them evenly and prevent clumping.
- Bring to a gentle boil. Once all the potatoes are added, bring the mixture to a gentle boil, stirring occasionally to prevent sticking or scorching. The sauce will begin to thicken as the potatoes release their starch.
- Stir in the Parmesan. Add the grated Parmesan cheese and stir until fully incorporated.
- First bake. Transfer the pan to the oven and bake uncovered for 30 minutes, or until the potatoes are just tender and most of the liquid has reduced.
- Add the cream. Pour the gently warmed heavy cream evenly over the potatoes. Return the pan to the oven and bake for 15 more minutes.
- Top with cheese. Sprinkle the shredded marbled jack cheese evenly over the top. Bake for another 15 minutes, or until the cheese is melted, bubbly, and lightly golden.
- Rest before serving. Remove from the oven and let the potatoes rest for 20–30 minutes before serving. This helps the sauce set and gives the gratin its creamy texture.
Equipment

Le Creuset Enameled Cast Iron Signature Braiser, 3.5 qt., Sea Salt
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Rachael Ray Stainless Steel Box Grater (Teal Blue)
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13 Piece Stainless Steel Measuring Cups and Spoons Set
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ThermoWorks Hi-Temp Silicone Spoonula
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- Vegetable broth can be replaced 1:1 with chicken broth.
- Chinese mustard can be replaced 1:1 with Dijon mustard.
- Mascarpone can be replaced 1:1 with cream cheese.
- Freshly grated Parmesan can be replaced 1:1 with grated canister Parmesan, though the texture may be slightly grainier.
- White pepper can be replaced 1:1 with black pepper.
- Marbled jack cheese can be replaced 1:1 with cheddar.
- Yellow potatoes work especially well here because their creamy texture and starch content help create a more traditional gratin texture.
- Do not rinse the sliced potatoes. Their natural starch helps thicken the sauce without added flour.
- For make-ahead prep, bake through the first bake step, cool slightly, cover, and refrigerate up to 24 hours. When ready to finish, remove from the refrigerator 30 minutes before baking, add the warm cream, and continue with the remaining steps.
- Prep Time: 20 minutes
- cooling: 20 minutes
- Cook Time: 1 hour
- Category: Side Dish
- Method: Baking, One Pot, stovetop
- Cuisine: American, French