White Castle Sliders Copycat Recipe

If you've ever found yourself in the White Castle drive-thru after a long night out, then you're familiar with the delicacy that is a White Castle slider. There really are few fast food burgers quite like it, with its miniature, squarish shape instantly recognizable. If you've ever enjoyed one of these beefy, oniony, ultra-savory little sammies, you know exactly why White Castle retains such a fan base of people who regularly flock to snag a slider or two (or five).

Of course, there are only so many White Castles in the world, and if you're anything like recipe developer Patterson Watkins, then you tragically don't live near one. "I, unfortunately, live several miles away from a White Castle," Watkins laments. Luckily, her copycat recipe is just the solution: "When those cravings hit, you gotta make some homemade concessions, and this recipe will definitely satisfy any and all White Castle cravings." Indeed, these homemade sliders are just as good as the real thing — possibly even better, because you can guarantee that they'll be fresh and served with all of your favorite toppings.

To achieve that heightened beefy flavor, you'll need beef, of course, along with a special ingredient: beef bouillon paste. "There's a unique element to White Castle burgers, an underlying savoriness, an umami-quality, that really sets these sliders apart from other fast food items. To mimic that flavor, we use beef bouillon," Watkins explains. You'll mix the bouillon right in with the other patty ingredients (yellow mustard, garlic powder, onion powder, salt, and pepper), which will "bring out those savory notes," as Watkins puts it.

Of course, there are other important components to a White Castle slider, so you'll also need some minced yellow onion, American cheese, pickles, and dinner rolls, which will serve as the buns.

To get started, you'll want to mix the beef, bouillon paste, mustard, garlic powder, onion powder, salt, and pepper in a large bowl. Watkins uses her hands for quick mixing, but you can use whatever tool works best for you.

Next up, grab a 9x13-inch baking sheet and line it with parchment paper. Place the ground beef mixture on the pan and squish it down into a thin, even layer, making sure to also press it into the corners. Use either a knife or bench scraper to score the meat into 12 even squares that you can easily break apart later — these will be the patties). Next, use the back of a wooden spoon to poke or dock the meat throughout, which will help reduce shrinkage and puffiness down the road when you cook it, not to mention replicate White Castle sliders' holes. Finally, cover the whole thing with plastic wrap and transfer it to the freezer for 3 hours, allowing the patties to freeze completely. "You want to make sure those patties are scored well and frozen," Watkins advises. "This will certainly help your burgers achieve that iconic White Castle square shape."

Once the patties are frozen, get the oven preheating to 425 F and remove the baking sheet from the freezer. Since you scored the patties earlier, they should snap apart with ease. Set the separated sliders aside for just a bit, then sprinkle the minced onion right onto that same parchment-lined baking sheet. Spread them out in an even layer, then place the patties on top of the onions.

Pop the baking sheet into the oven, allowing the onions and patties to cook for 15 to 20 minutes. While the process of baking the onions and patties is different from White Castle's griddling process, the method will yield similar results — without splattering your cooktop. "During the (fast food) cooking process, the patties sit atop a layer of onions. The steam/vapors rising off of the onions not only flavor the patties but subsequently cook them," Watkins explains. "We achieve this, not via a griddle, but by layering the onions and beef patties on a baking sheet and cooking them in the oven."

Take the baking sheet out of the oven and place a cut-side down bottom bun onto each individual patty. Then, place a top bun (also cut-side down) onto each bottom bun. Put the whole dish back into the oven for just about 3 minutes, or enough time to warm the buns. This process may look a bit funny, but the buns won't stay in this position for long.

For this next step, it may be handy to have a clean baking sheet or surface available to place the burgers. Remove the tray of patties and buns from the oven and set the top buns aside. Use a spatula to flip the patties and bottom buns right side up, scraping up as many onions as possible in the process, then place them onto a clean baking sheet, plate, or surface. (Inverting the entire tray of sliders won't work, as the pan juices would make the buns soggy.) Pile on the American cheese, pickles, and any other toppings you might enjoy. Add the top buns, and voila — you've got a White Castle slider, no drive-thru required.

As for side dishes, there's a pretty obvious choice here, as Watkins points out: "Crinkle-cut fries all the way!" Classic crinkle-cut fries will certainly give you that authentic White Castle experience, but any type of fry will pair well with these copycat sliders.