Au Gratin Potatoes
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These cheesy Au Gratin Potatoes are the most delicious potatoes ever! Coming from someone who loves potatoes, trust me when I say that this is a must-try recipe. This tested and perfected recipe is perfect for a holiday meal or family dinner. Just follow my step-by-step guide for perfect, creamy potatoes every time!
Table of contents
My grandma always made the best scalloped potatoes for Easter. When I got married, my husband brought his families au gratin potato recipe to the table. Now if you’re wondering “what is the difference between scalloped potatoes and au gratin?” It’s the addition of cheese!
Scalloped potatoes are made with layers of thinly sliced potatoes and a creamy sauce. Au grain potatoes also have the sliced potatoes and creamy sauce, but each layer also contains plenty of gruyere and sharp cheddar cheese. And of course, the entire dish is finished off with a delicious layer of melty cheese on top!
So now I’ve turned my Grandma Meme’s delicious family recipe for scalloped potatoes into the best au gratin potatoes, with the addition of cheese!
These potatoes are not to be missed at a family dinner, or holiday, like Thanksgiving or Christmas. They’re rich, decadent, creamy, and might just be the best potato side dish ever!
Ingredients
- Butter – to combine with the flour and make a roux, to help thicken the creamy sauce.
- All-purpose flour – combined with the butter to make the roux. You can also make this recipe without flour, and use cornstarch instead. You will only need half of the amount of cornstarch, because cornstarch has more thickening power than flour. For this recipe you’ll need 2 tablespoons of cornstarch to replace the 1/4 cup of flour.
- Onion – I recommend a yellow onion for it’s nice, neutral flavor. You could also use a Vidalia onion if you prefer a more mild, sweet flavor.
- Garlic – I always recommend fresh minced cloves for the best flavor.
- Chicken broth – or use vegetable broth to make the recipe vegetarian.
- Half and half – you could also use whole milk, but I prefer the added creaminess of the half and half.
- Salt + black pepper + fresh thyme – to season the sauce for the au gratin potatoes.
- Gold potatoes – while I have used russet potatoes to make this recipe a few times over the years, I’ve found that gold potatoes really work best. They’re so creamy, so after they cook in the rich, buttery sauce, the potatoes literally melt in your mouth!
- Sharp cheddar cheese – I always recommend sharp, over mild or medium cheddar cheese because of it’s rich and robust flavor that really shines through in the potatoes. For this recipe, you’ll want to freshly grate the cheese at home so that it melts perfectly into the potatoes.
- Gruyere cheese – Gruyere is a type of swiss cheese that is typically aged longer than a traditional swiss. I prefer gruyere, because like sharp cheddar, it has a stronger flavor, but you can also use swiss cheese in this recipe. Both gruyere and swiss cheese have a nutty, slightly sweet flavor, that pairs perfectly with the rich, bold cheddar cheese.
Instructions
I’ve included step by step photos below to make this recipe super easy to follow at home. For the full detailed recipe instructions and ingredient quantities, scroll to the recipe card at the bottom of this post.
Prepare the creamy sauce.
- Cook the onions and garlic. Melt butter in a large skillet on the stove over medium-high heat. Add diced onions and minced garlic. Cook for 4-5 minutes to soften the onions.
- Add flour. Sprinkle flour evenly over the onions and garlic in the skillet.
- Stir to combine everything. Cook for 1-2 minutes.
- Add chicken broth to the skillet and whisk to combine everything.
- Make it creamy. Reduce the heat on the stove to medium-low and slowly stir in the half and half. Continue stirring until the mixture comes to a gentle boil. You might have to increase the heat on the stove to medium heat to bring it to a boil.
- Season the sauce. Add salt, black pepper and fresh chopped thyme. Stir to combine everything. Turn the heat on the stove off and set the creamy sauce aside.
Prepare the casserole.
- Slice the potatoes. For this recipe, I highly recommend using a mandoline to thinly slice the potatoes. I used this mandoline on setting 3 to slice the potatoes, while wearing these cut-resistant gloves. If you’ve always been scared to use your mandoline for fear of slicing your finger, these gloves are perfect. I bought them for my husband to use with a meat slicer, but I’ve ended up using them more than him to slice veggies with my mandoline!
- Layer the potatoes in a baking dish. Grease a 9 inch by 13 inch baking dish with butter, or cooking spray. Layer ⅓ of the potatoes in the bottom of the casserole dish, sprinkle about ½ teaspoon salt evenly over the potatoes.
- Cover with the creamy sauce. Pour ⅓ of the creamy sauce over the potatoes. Sprinkle ½ cup shredded cheddar cheese and ½ cup shredded gruyere cheese over the sauce. Repeat with another layer of potatoes, salt, creamy sauce, and cheese, then again with the final layer of potatoes, salt and creamy sauce. Reserve the remaining cheese for later.
- Bake the potatoes. Cover the casserole dish with foil, then place the potatoes on the middle rack in a preheated oven set to 350°F and bake the potatoes for 45 minutes. Uncover the potatoes, top with the remaining cheese, and bake for an additional 20-30 minutes. Turn the oven from bake to broil on high and cook for an extra 2-3 minutes, or until the cheese begins to bubble. Do not walk away while the potatoes are under the broiler, you want to watch them and remove them when the cheese starts to bubble, with just a few golden brown spots. Remove the potatoes from the oven and let them rest for 15 minutes before serving. This will allow the creamy sauce to set around the potatoes and makes it easy to slice and serve the au gratin potatoes. Feel free to garnish the potatoes with fresh chopped parsley before serving, if you’d like.
Recipe notes
- Make sure to thinly slice the potatoes. I like using a mandoline and my handy cut-resistant gloves to make this process quick, easy and painless.
- Let the half and half sit out at room temperature for 15 minutes before using it in this recipe. Really cold milk, or half-and-half, will take longer to thicken in the sauce. Simply set the half and half on the counter before starting this recipe. By the time you’re ready to use the half and half in the creamy sauce, it will be good to go!
- Always shred your own cheese. I always recommend shredding your own cheese for the best flavor. Bagged pre-shredded cheeses have additives and they will not melt as well as freshly-grated cheese.
- To enhance the flavors of the creamy sauce, add 1-3 dashes of Tabasco or ½ teaspoon cayenne pepper with the salt, thyme and black pepper. This is an old chef’s trick used to enhance the flavors of a creamy sauce. The richness of the sauce will be enhanced by adding just a few dashes of hot sauce to the creamy sauce. Don’t worry, it won’t make this dish spicy, it’s just there as a flavor enhancer!
- To make this recipe gluten free, replace the 1/4 cup of flour in the creamy sauce with 2 tablespoons of cornstarch.
- This recipe will serve 8-10 people as a side dish at a holiday meal with 1-2 other side dishes. If serving this as the only side dish with a meal, it will serve 6-8 people.
Make ahead and storage tips
You can make the recipe ahead of time and store it in the fridge, covered, for up to 24 hours before baking and serving the au gratin potatoes.
Store leftover au gratin potatoes in the refrigerator for up to 6 days in an airtight container.
To reheat the leftovers in the oven, place the potatoes in an oven-safe dish and cover with aluminum foil. Reheat at 350°F for 20-25 minutes, or until heated through.
To reheat them in the microwave, place one serving of potatoes on a microwave-safe plate and reheat for 2 minutes.
To freeze cooked au gratin potatoes, allow them to cool completely to room temperature. Place them in a freezer-safe bag or airtight container. Freeze for up to 3 months. I always recommend thawing the au gratin potatoes overnight in the fridge before heating them up.
To reheat frozen au gratin potatoes, once they’ve thawed in the refrigerator, place them in an oven-safe pan, cover and heat for 25-30 minutes in a 350°F oven. Uncover and heat for an additional 5-10 minutes.
What to serve them with
These potatoes are an excellent addition to a holiday meal, like Easter, Thanksgiving or Christmas. If you’d like to serve them at the holidays, I recommend pairing the au gratin potatoes with any of these impressive main dishes.
- Honey Baked Ham
- Corned Beef
- Beef Wellington
- Roasted Prime Rib
- Smoked Turkey Breast
- Cranberry Glazed Turkey Breast
- Smoked Prime Rib
If you want to make an easy meal anytime of the year, serve this au gratin potatoes recipe as a side dish with any of these easy main dishes.
More side dish recipes
Try these other delicious side dishes for your next weeknight dinner or holiday meal!
Au Gratin Potatoes
Ingredients
- ¼ cup butter
- 1 cup onions, diced
- 2 cloves garlic, minced
- ¼ cup flour, or 2 tablespoons cornstarch
- 1 cup chicken broth, or vegetable broth
- 2 cups half and half, or whole milk
- 1 teaspoon salt, + more to season the potatoes
- ½ teaspoon black pepper
- 1 teaspoon fresh thyme leaves
- 3 pounds Yukon gold potatoes, thinly sliced with a mandoline
- 2 cups shredded cheddar cheese
- 2 cups shredded gruyere cheese
Instructions
Make the creamy sauce.
- Melt the butter in a large skillet on the stove over medium-high heat.
- Add the diced onions, cook for 4 minutes, then add the minced garlic and cook for an additional minute.
- Add the flour to the skillet, stir to combine everything, and cook for an additional 1-2 minutes.
- Add the chicken broth to the skillet and whisk to combine everything.
- Reduce the heat on the stove to medium-low and slowly stir in the half and half.
- Continue to cook, while stirring, until the mixture comes to a gentle boil.
- Stir in the salt, thyme and black pepper. Remove the creamy sauce from the heat and set it aside.
Prepare the potatoes.
- Preheat the oven to 350°F.
- Thinly slice all of the potatoes using a sharp knife or mandoline. I used this mandoline on setting 3 to slice the potatoes, while wearing these cut-resistant gloves.
- Grease a 9” x 13” casserole dish with butter or cooking spray.
- Place ⅓ of the potatoes in the bottom of the prepared casserole dish, sprinkle about ½ teaspoon salt evenly over the potatoes, then pour ⅓ of the sauce over the potatoes. Sprinkle ½ cup shredded cheddar cheese and ½ cup shredded gruyere cheese over the sauce.
- Repeat another layer of potatoes, salt, cream sauce and cheese, then another layer of potatoes, salt and cream sauce. Reserve the remaining cheese for later.
- Cover the casserole dish with a large piece of aluminum foil and bake for 45 minutes.
- Uncover the baking dish, sprinkle the remaining 1 cup cheddar cheese and 1 cup gruyere cheese over the potatoes, and bake for an additional 20-30 minutes.
- Turn the oven from bake to broil and continue cooking 2-3 minutes, or until the top of the cheese starts to bubble.
- Remove from the oven and let the potatoes rest for 15 minutes before serving.
Notes
- Let the half and half sit out at room temperature for 15 minutes before using it in this recipe. Really cold milk, or half-and-half, will take longer to thicken in the sauce. Simply set the half and half on the counter before starting this recipe. By the time you’re ready to use the half and half in the creamy sauce, it will be good to go!
- Always shred your own cheese. I always recommend shredding your own cheese for the best flavor. Bagged pre-shredded cheeses have additives and they will not melt as well as freshly-grated cheese.
- To make this recipe gluten free, replace the 1/4 cup of flour in the creamy sauce with 2 tablespoons of cornstarch.
- This recipe will serve 8-10 people as a side dish at a holiday meal with 1-2 other side dishes. If serving this as the only side dish with a meal, it will serve 6-8 people.
- You can make the recipe ahead of time and store it in the fridge, covered, for up to 24 hours before baking and serving the au gratin potatoes.
- Store leftover au gratin potatoes in the refrigerator for up to 6 days in an airtight container.
Nutrition Facts
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