Gramma’s Creamy & Cheesy Au Gratin Potatoes

Author: Laura Bennett Published: 02/12/2026

When I think back to my childhood holidays, they always felt extra special thanks to my dad’s family. They knew how to throw the best gatherings—tables loaded with food and plenty of laughter—and I was always so excited to dress up and join in.

At these big family celebrations, you’d often find creamy mashed potatoes dusted with paprika, an array of at least four kinds of pies, and of course, my dad’s famous cheesy, creamy au gratin potatoes. His version was packed with layers of thinly sliced potatoes, melty cheese, tender onions, and a crisp cheesy crust on top. Without fail, those potatoes were my absolute favorite holiday indulgence—always the first thing I piled high on my plate!

Today, I’m sharing this beloved recipe in memory of my dad, who passed away just over fifteen years ago. He was such an incredible cook, and sharing his love of food with you feels like keeping a bit of him alive in the kitchen. I hope you give these potatoes a try—they’re perfect for Thanksgiving dinner, Easter brunch, or simply a cozy Sunday dinner alongside roast chicken or maple-glazed salmon. This dish is pure, warming nostalgia baked right into a pan of creamy, cheesy comfort.

This cozy, crowd-pleasing side dish is inspired by my dad’s signature holiday meals. Picture delicate layers of thinly sliced Yukon Gold potatoes baked in a super creamy, triple-cheese sauce until tender and golden brown. It’s full of those warm, comforting flavors that remind you of family dinners, yet the method is simple enough for a weeknight meal too.

As you scroll through, you’ll find an easy, step-by-step guide for putting everything together, tips on slicing potatoes evenly for perfect cooking, helpful swaps for cheeses or even swapping in sweet potatoes, and advice for prepping ahead or storing leftovers. Along the way, plenty of photos help you feel confident that you’re crafting a beautiful, delicious side that feels special but never fussy.

Comfort Food at Its Best

These au gratin potatoes hit all the right notes for comfort food: ultra creamy, loaded with rich, layered cheese flavors (thanks to three different cheeses), and buttery Yukon Golds baked until tender and golden on top. The process is straightforward—a classic cheese sauce poured over neatly arranged potato slices—so you end up with a dish that looks and tastes elevated without extra effort. For a similar, ultra-creamy potato bake, try these cheesy scalloped potatoes.

Major crowd-pleaser: rich, cheesy, and comforting—a nostalgic side that shines at holidays or any large family gathering.
Super customizable: swap cheeses, throw in bacon or ham, use sweet potatoes, or add a crunchy breadcrumb topping.
Make-ahead friendly: you can prep this dish up to three days in advance; refrigerate assembled and bake when you’re ready (just add some extra bake time if it’s cold).
Easy leftovers: keeps well for up to five days in the fridge and reheats like a dream.
Simple pantry staples and basic kitchen tools (think mandolin, box grater, whisk) make this an approachable, impressive side dish.

Pantry & Cheese Checklist

Yukon Gold potatoes: thinly sliced
Onion: thin slices
Salted butter
All-purpose flour (or whole wheat or 1:1 gluten-free flour)
Unsweetened almond milk (or regular dairy milk)
Sharp cheddar cheese
Gruyere cheese
Freshly grated Parmesan cheese
Garlic powder
Salt
Black pepper
Fresh parsley (for finishing)

How to Assemble and Bake

Preheat oven to 375°F and grease a 2‑quart square casserole dish or an 8×12 baking dish.
Thinly slice Yukon Gold potatoes about 1/8 inch thick (use a mandolin if available).
Thinly slice an onion.
Arrange potato slices in three neat, slanted rows in the prepared dish, slipping onion slices between and on top and leaving a bit of space between slices.
Melt salted butter in a saucepan over medium heat.
Whisk in all-purpose flour to form a roux.
Slowly whisk in milk (almond or regular) until the sauce thickens.
Stir in grated sharp cheddar, grated Gruyere, and grated Parmesan until melted and smooth.
Season the cheese sauce with garlic powder, salt, and black pepper and taste to adjust seasoning.
Pour the cheese sauce evenly over the arranged potatoes and onions, ensuring all layers are coated.
Cover the dish tightly with foil and bake for about 45 minutes, until potatoes are tender.
Remove the foil, sprinkle additional cheese on top, and bake uncovered until golden, bubbly, and the top is crisped to your liking.
Garnish with chopped fresh parsley before serving.

Cooking Tips & Serving Notes

Slice potatoes evenly. Aim for slices about 1/8 inch thick to get perfect cooking all the way through. A mandolin slicer seriously helps here and saves time.
Don’t pack too tight. Give your potato slices a bit of wiggle room and arrange them slightly slanted. Slip in onion slices between and on top wherever you can fit them for extra flavor.
Grate cheese fresh. Skip pre-shredded cheese because fresh-grated melts smoother and gives your sauce a much creamier texture.
Taste and adjust seasoning. Once your cheese sauce is mixed, taste it before pouring. Add more salt or pepper if needed to balance the flavors, since it will coat a big batch of potatoes.

Serve these au gratin potatoes alongside your favorite roasted meats like herb-roasted chicken, maple-glazed salmon, or juicy pork chops for a cozy, crowd-pleasing meal. They also shine next to a simple green salad like this Broccoli Salad or steamed vegetables to balance all that cheesy richness.

If you’re bringing a dish to a holiday potluck, this will be the one everyone asks for seconds on. Plus, it reheats well the next day for easy lunches or dinners—comfort food for days!

Flavor Swaps and Add-Ins

Add bacon or ham. For a smoky, savory twist, fold in 6 to 8 ounces of cooked, chopped bacon or ham either mixed into the cheese sauce or layered on top before baking.
Switch up your cheeses. Don’t have Gruyere? No problem! Use extra sharp cheddar, smoky Gouda, or even a pepper Jack for a hint of heat to suit your family’s tastes.
Sprinkle breadcrumbs. If you like a crunchy finish, toss some breadcrumbs or crushed Ritz crackers over the top after pouring the cheese sauce and before baking.
Use sweet potatoes. Try this recipe with sweet potatoes for a naturally sweeter, slightly different flavor that’s equally delicious. For a lower-carb veggie swap with the same creamy, cheesy vibe, try our Cheesy Cauliflower Bake.

Swap cheeses: Mix and match what you have on hand—smoked gouda, fontina, or even a little mozzarella will work nicely.
Add meat: Crispy bacon or diced ham stirred in or layered on top gives a savory punch everyone will love, or fold in tender sautéed leeks for mellow sweetness.
Try sweet potatoes: Sweet and creamy, sweet potatoes give this a fun twist that still pairs brilliantly with the cheesy sauce.
Crispy topping: For a crunchy finish, sprinkle panko breadcrumbs or crushed crackers on top before the final bake.

Make-Ahead and Leftover Care

You can definitely get ahead by assembling these cheesy au gratin potatoes up to three days before baking. Simply layer the potatoes, pour the sauce over, cover the pan tightly with foil, and stash it in the fridge until you’re ready to bake. When baking from chilled, give yourself about 15 to 20 extra minutes in the oven so everything heats through and gets bubbly.

To store: Keep leftovers in airtight containers or cover the whole pan tightly and refrigerate. They’ll stay fresh and tasty for up to 5 days.
To reheat: Warm individual portions in the microwave or reheat the whole pan in the oven until heated through and inviting.

Got leftovers? No worries! These au gratin potatoes keep really well in the fridge when stored in airtight containers or covered tightly with foil. They’ll stay fresh and tasty for up to 5 days, making for easy weekday meals after a festive weekend.

If you want to freeze leftovers, portion them into freezer-safe containers and thaw in the fridge before reheating. This way, you can enjoy your dad’s comforting au gratin anytime you crave that cozy, cheesy goodness.

Life gets busy, I know! That’s why I love that you can fully assemble this dish up to three days ahead. Just layer the potatoes, pour the cheese sauce over, cover the pan tightly with foil, and chill. When it’s go-time, bake from cold but add around 15-20 minutes to the baking time so everything warms evenly and bubbles up beautifully. If you prefer a truly hands-off option on busy days, this slow cooker potato soup with frozen potatoes delivers the same cozy comfort with set-it-and-forget-it ease.

This is a total game-changer for holiday cooking or when you want a no-stress weeknight side that feels special. For another make-ahead side that freezes and reheats beautifully, try Brazilian Cheese Bread.

Common Questions About Au Gratin

People often get a little confused about the difference between classic au gratin potatoes and scalloped potatoes. Usually, au gratin has a cheesy sauce between each layer of thinly sliced potatoes and sometimes breadcrumbs on top. Scalloped potatoes tend to use a creamier sauce made with butter and broth, usually without cheese. Honestly though, both are comfort food favorites—and they pair wonderfully with easy homemade bread—so you can call them as you like!

In this recipe, I’m skipping the breadcrumbs and heavy cream for a lighter feel, adding savory sliced onions, and packing in extra cheesy goodness with three different cheeses.

Can I use regular milk instead of almond milk? Absolutely! Whole, 2%, or skim milk all work perfectly in this recipe. Feel free to use what you have on hand.

How thin should I slice the potatoes? About 1/8 inch thick is ideal for even, tender cooking. A mandolin is a huge help for speed and uniformity.

Can I make this dairy-free or vegan? To keep it dairy-free, swap the butter for a plant-based alternative and choose vegan cheeses that melt well. The texture will be a little different but still delicious!

Do I have to use Gruyere cheese? No worries if you don’t have it! Sharp cheddar alone, or with other cheeses like gouda or mozzarella, works well too.

Can I assemble and freeze this dish? Yes! Assemble as usual, then cover tightly and freeze. Thaw in the fridge before baking, adding extra time to cook through.