Cheesy Potato Gratin
Thinly sliced yellow potatoes baked in a creamy sauce with sharp cheddar, Swiss, and Parmesan. A rich, comforting side dish with tender potato layers and a golden cheese top.
Servings 10 servings
Equipment
- 9x13 casserole dish
- baking sheet
- aluminum foil
- saucepan
- measuring cups & measuring spoons
- whisk or silicone spatula
- cutting board
- sharp knife
- Mandoline slicer with hand guard (optional)
Ingredients
- 3 pounds yellow potatoes washed, unpeeled, and sliced 1/8 inch thick
- 1 1/2 tablespoons butter plus more for greasing the dish
- 2 –3 cloves garlic minced
- 2 cups heavy cream
- 1 teaspoon salt
- 1/2 teaspoon black pepper
- 3/4 teaspoon paprika
- 1 1/3 cups shredded sharp cheddar cheese
- 1/2 cup grated Parmesan cheese
- 1 cup shredded regular Swiss cheese or Gruyère or additional cheddar
Instructions
- Preparing the Potatoes and Dish
- Preheat the oven to 350°F. Butter a 9x13x2-inch casserole dish. Line a baking sheet with foil and set aside.
- Thoroughly wash the potatoes. Leave the skins on and slice approximately 1/8 inch thick, keeping the slices as even as possible.
- Making the Cheese Sauce
- Melt the butter in a saucepan over medium-low heat. Add the minced garlic and cook for approximately 30 seconds, stirring.
- Add the heavy cream, salt, pepper, and paprika. Heat until steaming, stirring occasionally. Remove from the heat.
- Add the cheddar, Parmesan, and Swiss cheeses one at a time, stirring until each addition is melted before adding the next. Stir until the sauce is smooth.
- Layering and Baking
- Arrange half the potato slices evenly in the prepared casserole dish. Pour half the cheese sauce over the potatoes.
- Arrange the remaining potatoes over the first layer and pour the remaining sauce evenly over them. Leave at least 1/2 inch of space below the rim. If necessary, place any excess in a separate small baking dish.
- Cover tightly with foil. Set the casserole on the foil-lined baking sheet to catch any drips.
- Bake for 60 minutes. Remove the foil and bake for approximately 30 minutes longer, until the top is golden and a knife slides easily through the potatoes in the center.
- If the top browns before the potatoes are tender, loosely cover with foil and continue baking until done.
- Let stand for 15 minutes before serving so the sauce can thicken slightly.
Notes
Potatoes: I prefer yellow potatoes for their sweeter, richer flavor. I find their flavor blends nicely with the cheese sauce without being overwhelmed by it.
Peeling: I leave the skins on. Wash the potatoes thoroughly before slicing. You may peel them if preferred.
Even slices: Aim for slices approximately 1/8 inch thick so the potatoes cook evenly. If using a mandoline, use its hand guard.
Swiss cheese: We prefer regular Swiss cheese—the kind with larger holes—rather than baby Swiss. Gruyère or additional sharp cheddar can be substituted in the same amount.
Dish capacity: Use a 9x13x2-inch casserole dish and leave at least 1/2 inch below the rim for bubbling. Bake any excess in a separate small dish rather than overfilling.
Catch drips: Place the casserole on a foil-lined baking sheet to catch any cheese sauce that bubbles over.
Baking time: Approximately 90 minutes is an estimate. The thickness of the potato slices and the baking dish can affect the cooking time. Check the center with a knife; the potatoes should be tender throughout.
Browning: If the top becomes golden before the potatoes are tender, loosely cover with foil and continue baking.
Resting: Let stand for 15 minutes before serving to allow the sauce to thicken slightly.
Servings: Makes approximately 10 side-dish servings, depending on portion size.
