Dad’s Creamy & Cheesy Au Gratin Potatoes are a classic comfort dish that’s all about tender, thinly sliced potatoes baked in a rich, creamy cheese sauce until golden and bubbly on top. The combination of creamy texture with the crispy cheesy edges is what makes this dinner favorite so special and satisfying.
I love making this recipe because it reminds me of family dinners where everyone reaches for seconds — it’s simple but has that homemade feel that makes you feel warm and happy inside. My tip is to use a sharp cheddar for the sauce to get that nice cheesy kick, and don’t be shy about letting the top get perfectly browned and crispy.
We often serve these potatoes alongside roasted chicken or a fresh green salad, making dinner feel complete without too much fuss. Whenever I make Dad’s Au Gratin Potatoes, it feels like a little celebration at the table, bringing everyone together over a dish that’s both comforting and delicious.
Key Ingredients & Substitutions
Potatoes: Yukon Gold potatoes are my favorite for this dish because they hold their shape well and have a creamy texture. You can also use Russet potatoes for a fluffier, softer result. Just slice them thin for even cooking.
Cheese: Sharp cheddar adds a nice tang and richness. Gruyère is optional but really deepens the flavor with its nutty character. If you can’t find Gruyère, Swiss or Fontina work well as substitutes.
Milk: Whole milk is best for a creamy sauce. You can swap with 2% milk if needed, but avoid skim to keep the sauce rich and smooth. Warming the milk before adding helps prevent lumps in the sauce.
Butter and Flour (Roux): These make the base for the creamy sauce. Butter gives richness and flour thickens. Be sure to cook the roux for a minute or two to avoid a raw flour taste before adding milk.
How Can I Make the Cheesy Sauce Smooth and Lumpy-Free?
Making a creamy cheese sauce without lumps is key to this recipe. Here’s how I do it:
- Start by melting butter and cooking garlic briefly – don’t let it brown.
- Whisk in the flour and cook for a couple of minutes, stirring all the time, so the raw flour flavor cooks out.
- Add warm milk slowly, whisking constantly to combine smoothly.
- Keep stirring the sauce while it cooks to thicken—this helps prevent lumps.
- Remove from heat, then stir in the cheese gently until melted.
If the sauce looks too thick before cheese, add a splash more warm milk. Stir gently but well, and you’ll get that velvety, creamy sauce perfect for coating the potatoes.
Equipment You’ll Need
- 9×13-inch baking dish – I like this size because it holds all the potatoes evenly and is easy to serve from.
- Large pot – perfect for boiling and slicing the potatoes once cooked.
- Medium saucepan – essential for preparing the cheese sauce; it helps control the heat and prevents burning.
- Whisk – makes stirring the sauce smooth and lump-free, which is key for a creamy texture.
- Cutting board and sharp knife – for slicing potatoes thinly and evenly, ensuring they cook uniformly.
Flavor Variations & Add-Ins
- Swap cheddar for pepper jack or mozzarella to add different cheesy flavors or a gooey texture.
- Add cooked bacon bits or ham between layers for a meaty, smoky twist.
- Mix in sautéed onions, mushrooms, or spinach to boost the veggie content and add flavor variety.
- Sprinkle fresh herbs like thyme or rosemary on top before baking for added aroma and freshness.
Dad’s Creamy & Cheesy Au Gratin Potatoes
Ingredients You’ll Need:
For The Potatoes:
- 3 pounds Yukon Gold or Russet potatoes, peeled and thinly sliced
For The Cheese Sauce:
- 3 tablespoons unsalted butter
- 3 tablespoons all-purpose flour
- 3 cups whole milk, warmed
- 1 ½ cups sharp cheddar cheese, shredded
- 1 cup Gruyère cheese, shredded (optional for extra depth)
- 2 cloves garlic, minced
- 1 teaspoon salt
- ½ teaspoon freshly ground black pepper
- ¼ teaspoon nutmeg (optional)
For Garnish:
- 2 tablespoons fresh parsley or thyme, chopped
How Much Time Will You Need?
This recipe takes about 20 minutes to prepare and assemble, then about 1 hour and 15 minutes to bake. You’ll also want to let it rest 10 minutes before serving, so plan for about 1 hour 45 minutes from start to finish.
Step-by-Step Instructions:
1. Prepare Your Oven and Dish:
Preheat your oven to 350°F (175°C). Butter a 9×13-inch baking dish to prevent sticking and add richness to the dish.
2. Make the Cheese Sauce:
In a medium saucepan over medium heat, melt the butter. Add the minced garlic and cook for about 1 minute until fragrant but not browned. Stir in the flour and whisk constantly, cooking for 1-2 minutes to form a roux. Gradually add the warmed milk while whisking continuously to avoid lumps. Keep stirring and cooking until the sauce thickens and can coat the back of a spoon, about 5-7 minutes. Remove from heat and stir in 1 cup of cheddar cheese and all the Gruyère (if using) until melted and smooth. Add salt, pepper, and nutmeg for flavor.
3. Layer the Potatoes and Sauce:
Arrange a layer of the thinly sliced potatoes evenly in the baking dish. Pour some of the cheese sauce over the potatoes to cover them. Repeat layering potatoes and sauce until all are used, finishing with a layer of sauce on top. Sprinkle the remaining ½ cup of cheddar cheese over the top.
4. Bake and Finish:
Cover the dish with aluminum foil and bake for 45 minutes. Then remove the foil and bake for an additional 25-30 minutes, or until the top is golden brown and bubbly and the potatoes are tender when pierced with a fork.
5. Rest and Garnish:
Let the dish rest for 10 minutes before serving. Sprinkle fresh chopped parsley or thyme on top for a fresh, vibrant finish.
Can I Use Frozen Potatoes for Au Gratin?
Fresh potatoes work best because they hold their shape and texture. If using frozen, thaw completely and pat dry to avoid excess moisture that can make the dish watery.
Can I Make Au Gratin Potatoes Ahead of Time?
Yes! Assemble the dish up to the baking step, cover tightly, and refrigerate for up to 24 hours. Bake as directed, adding an extra 10-15 minutes if baking straight from cold.
How Should I Store Leftovers?
Store leftovers in an airtight container in the fridge for up to 3 days. Reheat covered in the oven at 350°F until warmed through to keep the sauce creamy and prevent drying out.
Can I Substitute the Cheese?
Definitely! Sharp cheddar is key for flavor, but you can swap Gruyère with Swiss, Fontina, or even a mild mozzarella for a different taste and texture.