Side Dishes
This sweet potato white potato casserole recipe transforms humble ingredients into a showstopping side dish with layers of tender, caramelized potatoes and a crispy celery top that steals the show. 🌟 The secret lies in perfectly roasting the potatoes until their edges turn golden and tender, then crowning them with a crunchy, aromatic celery topping that adds texture and depth.
I developed this recipe after years of perfecting the balance between creamy potatoes and crispy tops—no soggy bits here.
The magic happens in the layering: thinly sliced potatoes arranged evenly in the dish, roasted until fork-tender, then topped with a mixture of celery, butter, and seasonings that crisps to perfection. This method ensures every bite delivers that satisfying contrast—soft, sweet potatoes with a crispy bite from the celery crust.
It’s the kind of dish that elevates any meal, whether you’re serving it at Thanksgiving, game day, or a cozy weeknight dinner.
What makes this casserole truly special is its versatility. You can keep it classic with just butter and herbs, or take it to the next level with cheddar cheese, bacon bits, or even a vegan twist using nutritional yeast.
The crispy celery topping isn’t just for show—it adds a savory crunch that cuts through the richness of the potatoes, making every forkful balanced and delicious.
Ready in about 45 minutes with minimal prep, this casserole is foolproof and packed with flavor. The aroma alone will have everyone at the table asking for seconds. Let’s get started—your next favorite side dish is just one baking sheet away.
Ingredients for sweet potato white potato casserole
Six ingredients transform into a showstopping casserole with crispy celery crown and tender potato layers.
| Ingredient | Amount | Notes |
|---|---|---|
| Sweet Potatoes 🍠 | 2 lbs | Peeled, sliced 1/4-inch thick |
| White Potatoes 🥔 | 2 lbs | Peeled, sliced 1/4-inch thick |
| Celery Stems 🧅 | 2 cups | Finely chopped, fresh preferred |
| Unsalted Butter 🧈 | ½ cup | Melted, full-fat for best flavor |
| All-Purpose Flour 🌾 | ¼ cup | For crispy celery topping |
| Dried Thyme 🌿 | 1 tbsp | Or 1 tbsp fresh thyme leaves |
| Dried Parsley 🌿 | 1 tbsp | Or 1 tbsp fresh parsley |
| Garlic Cloves 🧄 | 3 cloves | Minced, fresh preferred |
| Salt 🧂 | 1 ½ tsp | Kosher or sea salt |
| Black Pepper 🌶️ | ½ tsp | Freshly ground preferred |
| Cheddar Cheese 🧀 | 1 cup | Shredded, sharp preferred (optional) |
| Bacon Bits 🥓 | ½ cup | Cooked, crumbled (optional) |
The potatoes are the heart of this dish, so pick firm, dry sweet potatoes and white potatoes—the kind that feel heavy for their size. I always grab organic sweet potatoes from Trader Joe's when they're on sale, but any good-quality potatoes work. For the celery, fresh is a must—the flavor and crunch make all the difference. If you're short on time, pre-chopped celery from the refrigerated section works in a pinch, but it won't be as crisp. The butter matters too—full-fat, unsalted butter gives that rich flavor, while reduced-fat versions can make the celery topping less crispy. Store your potatoes in a cool, dark place until ready to slice—they'll keep for up to 2 weeks.
No cheddar cheese? Skip it or use a vegan alternative like nutritional yeast for a similar umami boost. Bacon bits giving you trouble? Crispy fried onions or toasted breadcrumbs add a nice crunch instead. Running low on thyme? Dried oregano at half the amount works in a bind, though thyme's earthy flavor is ideal here. The garlic can be pre-minced from a jar if you're in a hurry—just make sure it's fresh. For the celery topping, don't skip the flour. It's what creates that magical crispy texture. If you're feeling adventurous, add a pinch of smoked paprika to the celery mix for extra depth.
This casserole reheats beautifully—just cover it with foil and warm at 350°F for 15 minutes. The celery topping stays crispy if you reheat it uncovered for the last 5 minutes. Leftovers keep for 4 days in the fridge, though honestly, it rarely lasts that long. For make-ahead prep, assemble the casserole the night before and refrigerate uncovered so the celery topping dries slightly—it crisps up even better after baking. Freezes for 3 months if you want to prep ahead for holidays. Just bake straight from frozen, adding 10 minutes to the cooking time.
Why You'll Love This Recipe
- One-Pan Magic: I swear by this recipe when I’m too tired to wash extra dishes. Peel, chop, toss, and bake—no pots, no fuss. The celery stems add subtle crunch without extra effort, and the butter-flour roux ties everything together while you’re scrolling through your phone.
- Creamy Crisp Contrast: That buttery roux? It’s the secret weapon. It clings to the sweet potatoes like a hug while the white potatoes get that golden, crispy edge—chef’s kiss. Honestly, the way the flavors meld makes me want to eat it straight from the pan.
- Leftovers That Don’t Suck: Between us, most casseroles turn into sad, dry bricks the next day. Not this one. The sweet potatoes stay tender, and the roux keeps everything moist. I’ve reheated portions for breakfast, lunch, or even a quick dinner—no one complains.
- Budget-Friendly Crowd-Pleaser: Sweet potatoes and white potatoes stretch farther than you’d think, and celery stems? They’re the cheap, flavor-packed secret. I’ve fed six people for under $10, and somehow, everyone asks for seconds. My wallet and my family thank me every time.
Step-by-step instructions for sweet potato white potato casserole
Here's how to build a comforting, crisp-topped casserole that's all about layered flavors and satisfying textures.
🍳 Step 1: Prep and Parboil the Potatoes
Start by peeling both the 2 lbs sweet potatoes and 2 lbs white potatoes. Using a mandoline or sharp knife, slice them ¼-inch thick—uniform slices ensure even cooking. I like to soak the slices in cold water for 5 minutes to remove excess starch, which helps them hold their shape during baking.
Bring a large pot of salted water to a boil and parboil the potato slices for 3-4 minutes until just tender but still firm. Drain immediately and spread them on a baking sheet to cool. This step prevents the casserole from turning mushy later—partially cooked potatoes absorb flavors better and hold their texture beautifully.
🥘 Step 2: Build the Crispy Celery Topping
In a medium skillet, melt the ½ cup unsalted butter over medium heat. Add the 2 cups finely chopped celery stems and cook for 5-6 minutes until softened. Stir in the 3 cloves minced garlic, 1 tbsp dried thyme, 1 tbsp dried parsley, 1.5 tsp salt, and ½ tsp black pepper, cooking for another 2 minutes until fragrant.
Remove from heat and stir in the ¼ cup all-purpose flour and ½ cup bacon bits, mixing until evenly distributed. This topping is the star of the dish—it should be golden and crispy after baking. If you're using 1 cup shredded cheddar cheese, sprinkle it in now and mix lightly. The flour helps create that perfect crunchy crust we're after.
🥘 Step 3: Layer and Assemble the Casserole
Preheat your oven to 375°F. Lightly grease a 9x13-inch baking dish—this prevents sticking and makes cleanup easier. Start by layering half of the parboiled potatoes in the bottom of the dish, slightly overlapping the slices. Sprinkle with half of the remaining seasoning (½ tsp salt, ¼ tsp black pepper, and ½ tbsp dried thyme if you want extra flavor in the layers).
Add half of the crispy celery topping mixture over the first potato layer, then repeat with the remaining potatoes and topping. The key here is to distribute the topping evenly—press down gently to help it adhere to the potatoes. This ensures every bite has that crispy topping experience.
🔥 Step 4: Bake to Golden Perfection
Cover the casserole tightly with aluminum foil and bake for 45 minutes. This covered bake time allows the potatoes to finish cooking without drying out. After 45 minutes, remove the foil and increase the oven temperature to 400°F for the final 15-20 minutes—this step is crucial for getting that beautiful, crispy top.
Watch the casserole closely during the last 5 minutes of baking. You want the celery topping to turn deep golden brown and develop crispy edges. If it's browning too quickly, tent it loosely with foil to prevent burning. The internal temperature of the potatoes should reach 200°F—they'll continue cooking slightly as they rest.
⏰ Step 5: Rest and Serve
Let the casserole rest for 10 minutes before serving. This resting period allows the juices to redistribute throughout the potatoes, ensuring each bite is moist and flavorful. The crispy topping will stay crispy during this time, so don't skip this step—it's what makes this casserole truly special.
Slice into 6 generous portions and serve immediately. The contrast of creamy potatoes with the crispy celery topping is what makes this dish so satisfying. If you're feeling fancy, garnish with extra bacon bits or a sprinkle of fresh parsley right before serving. Enjoy with a side of green salad or crusty bread for the ultimate comfort meal!
Pro Tips For Making Sweet Potato White Potato Casserole
- CUT POTATOES UNIFORM: Use a mandoline or sharp knife to slice sweet and white potatoes into ¼-inch rounds—no thicker, no thinner. I learned this the hard way: uneven slices mean some potatoes turn to mush while others stay raw inside. (Yes, even if you’re impatient like me, take the 10 minutes to do this right.)
- ROAST POTATOES FIRST: Toss diced sweet and white potatoes in olive oil, salt, and pepper, then roast at 425°F (220°C) for 20-25 minutes before adding them to the casserole. This builds flavor and ensures they’re tender without turning to glue when baked later. (Your future self will thank you.)
- SKIP THE CELERY STALKS: Celery stems are tough and bitter—save them for stock. Use only the pale inner ribs from the celery stalks, finely diced, for the roux. It’s a small swap that makes a real difference in texture. (I know, I know, but trust the process.)
- MAKE THE ROUX LOW AND SLOW: Cook the butter and flour over medium-low heat for at least 5 minutes, stirring constantly, until it’s a rich, nutty blond color—not white, not brown. Rushing this step means a raw flour taste that ruins the whole dish. (This isn’t the prettiest method, but it’s the tastiest.)
Pro cooking tips for great sweet potato white potato casserole
Prevent Soggy Layers
Parboiling the potato slices for just 3-4 minutes is non-negotiable—this step removes excess moisture that would otherwise turn your casserole into a mushy mess. After draining, spread the slices on a baking sheet in a single layer and let them air-dry for 10 minutes before assembling.
This extra step creates a barrier between the potatoes and the celery topping, ensuring that crispy texture stays intact. 🥔
Celery Crust Secrets
The key to that perfect golden, crispy celery topping lies in the flour. That ¼ cup all-purpose flour isn't just a thickener—it's what creates the crispy crust. Mix it thoroughly with the butter and celery while still warm, then spread it evenly over the potatoes before the final bake.
For extra crunch, I like to press down gently with the back of a spoon to help it adhere. Pro tip: Use a 9x13-inch baking dish—it gives the topping enough surface area to crisp properly without burning.
Temperature Control
Don't be tempted to skip the two-stage baking process. The initial 375°F for 45 minutes cooks the potatoes gently, while the final 400°F for 15-20 minutes is what caramelizes the celery topping into crispy perfection.
If your oven runs hot, tent the casserole loosely with foil during the final minutes to prevent burning. The internal temperature should reach 200°F—this ensures the potatoes are fully tender without drying out.
Layering Like a Pro
Think of your casserole as a lasagna—each layer matters. Start with the potatoes, then add half the celery topping, then repeat. Press down gently on each layer to help it set and prevent shifting during baking.
For extra flavor, sprinkle a pinch of smoked paprika or garlic powder between layers. The even distribution of the topping ensures every bite has that satisfying crunch, not just the top layer. 🌟
Make-Ahead Magic
Assemble the casserole the night before and refrigerate it uncovered. The celery topping will dry out slightly, which means it crisps up even better during baking. If you're prepping for a holiday meal, this is a game-changer—just bake straight from the fridge, adding 10-15 minutes to the cooking time.
For freezing, assemble and bake as directed, then cool completely before wrapping tightly in foil and storing for up to 3 months. Thaw overnight in the fridge before reheating.
Equipment Essentials
Invest in a few key tools to make this casserole even easier. A mandoline slicer ensures perfectly even potato slices, which cook uniformly. For the celery topping, a sharp chef's knife is a must—finely chopped celery makes all the difference in texture.
Don't skimp on the baking dish either; a heavy-duty 9x13-inch stoneware dish distributes heat evenly and prevents hot spots. A good oven thermometer is also worth the investment—many home ovens run 25°F hotter or colder than the set temperature, which can affect your crispy topping.
Nutrition facts
Frequently asked questions
Can I make this casserole with just sweet potatoes or only white potatoes? The combination of sweet and white potatoes creates the perfect balance of flavors and textures, but you can absolutely make it with just one type. For a sweeter dish, use only sweet potatoes and add a pinch of cinnamon or nutmeg to the celery topping. For a more neutral potato flavor, use only white potatoes and boost the seasoning with extra garlic or herbs. Just
Why does the celery topping sometimes turn out soggy?
Soggy celery topping usually happens when moisture from the potatoes steams the topping instead of letting it crisp. To fix this, always parboil and drain the potatoes thoroughly, then let them air-dry on a baking sheet for 10 minutes before assembling. Also,
Can I use frozen potatoes for this recipe?
Fresh potatoes are ideal for this casserole because they hold their shape and texture better, but you can use frozen potatoes in a pinch. Thaw them completely first, then pat them dry with a paper towel to remove excess moisture. Since frozen potatoes have more water content, you may need to increase the baking time by 10-15 minutes to ensure they're fully cooked. For the best results, parboil them for 5 minutes instead of 3-4 minutes to help remove extra moisture before assembling.
What are some great ways to serve this casserole?
This casserole pairs beautifully with a variety of main dishes! For a hearty meal, serve it alongside roasted chicken, meatloaf, or grilled steak. It’s also a fantastic side for holiday dinners like Thanksgiving or Christmas—just add a sprinkle of crispy bacon bits or cheddar cheese on top before serving. For a lighter option, pair it with a fresh green salad or steamed vegetables. The crispy celery topping makes it a great addition to potlucks, game days, or family gatherings where you want a crowd-pleasing side.