Sooo, this year's holiday dinner is about to get a whole lot creamier and comforting. I mean... just take a look at this. Rich and creamy potatoes au gratin, aka the ultimate comfort food, is made with sliced potatoes, cheese, and milk. It's the perfect side dish for the holidays or for dinner ANY DAY.
So if you know, then you know, that I am obsessed with potatoes. Give them to me baked, mashed, fried, roasted, au gratin, in a poutine, and basically prepared in any and every way that potatoes can be prepared. Potatoes au gratin are kind of my jam these days.
What are Potatoes Au Gratin?
Potatoes au gratin a rich and creamy potato dish made with layers of sliced potatoes baked in a creamy cheesy sauce. But wait, isn't that also called scalloped potatoes? Well no. These are actually two similar but different dishes. The distinguishing feature that sets it apart is cheese. That's right, scalloped potatoes does not have any cheese.
So let me ask you, which would you prefer? Potatoes au gratin or scalloped potatoes? For me, it's a no brainer. Cheese wins. Every time.
How to Make the Best Potatoes Au Gratin
So, the key to making the very best creamy potatoes au gratin is to keep in mind the following tips.
- Thinly sliced potatoes - the easiest way to get those perfect thin slices is to use a mandoline slicer. It saves you time from having to manually slice each potato with a knife, and by getting even slices you can be confident that the potatoes will cook evenly.
- Onions - the secret is the pan fry the onions with garlic. Most gratin potato recipes do call for onions but they are just thrown into the baking dish raw. Trust me on this one. Pan frying in butter just brings out the flavours in a whole different and better way.
- Whole milk - most recipes for potatoes au gratin use cream in the cheese sauce. I have opted for a slightly healthier version using milk. But, you want to make sure to use whole milk to still get that creaminess that is ever so crucial in this dish.
- Cheese - lots and lots of cheese! I used a combination of my favourite cheese - sharp white cheddar and Grana Padano cheese. The results are to die for (at least according to my taste palate). You could easily substitute these for other melty types of cheese like regular cheddar, Gruyère cheese, mozzarella, and Parmesan cheese.
- Bake for 90 minutes - yup, it really does take that long! You will also need to bake the potatoes covered for the first hour, and then uncovered for the final 30 minutes. This will get you that beautiful golden brown colour on top.
FAQ and Tips for Making Potatoes au Gratin
- Can I made potatoes au gratin in advance? Absolutely. Prepare everything into your casserole dish and cover it tightly with plastic wrap. Press the wrap directly on the potatoes to prevent them from browning, although some discolouration may happen on the top. Store in the refrigerator until you are ready to bake.
Rich and creamy potatoes au gratin is the ultimate comfort food made with sliced potatoes, cheese, and milk. It's the perfect side dish for the holidays.
- 2 pounds Yukon gold potatoes, peeled and thinly sliced
- 2 tablespoons unsalted butter
- ½ medium onion, diced finely
- 2 cloves garlic, minced
- 2 tablespoons all-purpose flour
- 1 and ½ cups whole milk
- ½ teaspoon salt
- ¼ teaspoon ground black pepper, or to taste
- 1 cup sharp white cheddar cheese, shredded
- ¼ cup Grana Padano cheese, shredded
- fresh green onions, chopped (optional, for garnish)
- Preheat oven to 375 F. Lightly grease a 9 x 9 inch baking dish. Layer potatoes in the baking dish.
- Melt butter in a large saucepan over medium heat. Add onion and garlic and cook until soft and translucent, about 3 minutes. Whisk in flour and continue to whisk until browned, about 30 seconds to 1 minute. Gradually whisk in milk, and add salt and pepper. Continuously whisk until mixture has thickened, about 2-3 minutes. Turn heat down to low and add cheeses and stir continuously until melted, about 30 seconds.
- Pour cheese sauce on top of the potatoes, and cover with aluminum foil. Place into oven and bake for 1 hour. Uncover and continue to bake for 20-30 minutes or until lightly browned and the potatoes are tender and mixture has thickened.
- Garnish with fresh ground black pepper and green onions (optional) and serve immediately.
- Prep Time: 20 minutes
- Cook Time: 1.5 hours
- Category: Side Dish