Scalloped Vs Au Gratin: Here's How These 2 Potato Dishes Differ

The breadth of tasty potato recipes truly has no limits — think vada pav sliders or repurposed super crispy potato peels. Approach the vegetable's preparation with care, and you can fry, boil, steam, roast, and saute spuds into delicious form. Dishes featuring this tuber run so varied, they even start to overlap, making delineation tricky. 

Take scalloped potatoes and potatoes au gratin. Past their distinct lingual roots, the two dishes often mistakenly get clumped together. Reference either name, and you can expect a batch of baked sliced potatoes held in a casserole-style dish. So to explain the dish's nuance, Food Republic spoke to Marissa Stevens, the recipe developer and founder of Pinch and Swirl.

According to her, the central distinction mostly comes down to one ingredient. "Au gratin includes cheese throughout the layers," while scalloped potatoes come "in a milk or cream sauce with little or no cheese." After all, the employed dairy plays a big role in these dishes: The use of butter, milk, and cream further impacts the resulting decadence. So, to figure out which dish you're in the mood for, start by considering the cheese.

Of the two, scalloped potatoes showcase the vegetable in a simpler style. The thin slices bake in a thick layer of dairy, with only the tops exposed to eye-catching browning. The rest turns into dense yet creamy bites of starchy goodness. The lack of cheese means there's no stretchy gooeyness, nor crisping in the pan. However, it does offer its own tender appeal. It's "like the difference between creamy pasta and baked mac and cheese," Marissa Stevens noted.

The precise ratios of dairy vary per recipe. Cooks employ combinations of cream, half and half, milk of differing fat percentages, butter, and even buttermilk. Most prefer a balanced mixture –  rich enough to add body to scalloped potatoes, but one that won't overwhelm the dish with decadence. Furthermore, it's essential to heat the dairy mixture before melding with the spuds. Especially with no cheese, such a technique kickstarts the loosening of starch, thereby binding the scalloped potatoes together.

The simplicity of the dish welcomes further ingredients. Take a spinach artichoke scalloped potato recipe, for example, replete with gentle earthiness — or amp up the savoriness with crumbled bacon. More simply, scalloped potatoes can also incorporate varying herbs, onions, or just a dash of paprika and garlic powder for subtler flavoring. Truth be told, lightly or even abundantly cheesy scalloped potato recipes circulate the internet, too — it's just not a traditional foundational component. So pinpoint your preferred combination of milk, cream, and butter to enjoy the dish in its most classic rendition.

Meanwhile, potatoes au gratin pivot the baked casserole into denser territory. The dish relies on the same template, but a generous helping of shredded cheese shakes up its appeal. Not only does this imbue a new flavor, but it also encases the starchy spuds in a mouthwatering crust. Even inside the dish, all the melting aids in creating structure. Subsequently, Marissa Stevens recommended this version for prepping ahead of time. "It reheats beautifully and holds its shape," she noted.

Chefs frequently add a few additional touches to highlight the all-around crunchier textural quality. Stevens recommended a breadcrumb topping, "which gives you a deeper crust and richer texture." Alternatively, during the last ten minutes of baking, she also likes to apply "a mix of shredded cheese and a few dots of butter" and cooks everything under the broiler to attain that golden brown finish.

When it comes to the fundamental cheese component, the possibilities are extensive. With its complex nutty flavor and easily-meltable composition, Gruyère is a common candidate. Other aged cheeses like Swiss or cheddar are also beloved for their flavor. However, recipes incorporate everything from mozzarella to Havarti and parmesan. Whether optionally embellished with ingredients like an herbed pumpkin potato gratin or kept plain, potatoes au gratin crisps up into a mouth-watering cheesy, custardy result.