The best 5-ingredient White Castle hamburgers

Depending on where you live, White Castle might be a regular favorite or part of the lore and legend only known about because of the Harold & Kumar movies. And yet, despite the fact that it only has fewer than 400 locations in only 13 states, this fast-food restaurant stands out in the sea of burger joints because of its tiny, almost bite-sized sliders. In fact, White Castle was the first fast-food hamburger chain to sell over one billion burgers!

If you're one of the unlucky many that don't have a White Castle near you, you can still find their products in the frozen aisle of most grocery stores. But, if you're like us, frozen hamburgers don't always sound too appealing. So we decide to crack to the code and make the perfect copycat White Castle sliders. After a few test batches, we came up with a method that makes sliders that almost look like the real deal. Better yet, they taste almost identical, too, and this recipe doesn't require a pantry full of ingredients or a ton of time to execute. Read on to find out how to make these delicious 5-ingredient White Castle hamburgers.

Gather the ingredients for these 5-ingredient White Castle hamburgers

Before we stopped by the grocery store to pick up our ingredients, we took a quick peek at White Castle's website. We were hoping to find a list of ingredients for their hamburgers. Unfortunately, the only resource they provided was an allergen statement, which informed us the burgers contain wheat. Luckily, White Castle also sells their sliders in the freezer section of most grocery stores, so we were able to get additional information about the individual ingredients.

The frozen sliders use a wheat flour bun, and the hamburger itself contains beef and dried onions. Although the pickle isn't included in the frozen product, we know the fast-food restaurants serve their sliders with a slice of pickle, so we added pickles to the list. Finally, we know from experience that the onions are soft, not crunchy, so we added water to our list to rehydrate the dried onions.

For a full list of ingredients, including step-by-step instructions and ingredient quantities, scroll down to the directions portion of this article.

What's the best beef to use for 5-ingredient White Castle hamburgers?

In our experience, 80/20 beef is the best choice for making hamburgers. Epicurious describes this number as the lean-to-fat ratio, so 80/20 beef is 80 percent lean meat and 20 percent fat. That might sound like a lot of fat, but it's necessary to keep the burger juicy as it cooks. The fat will render out of the beef when it's exposed to heat, surrounding the meat in the pan. That rendered fat not only keeps the meat tender, but it will also infuse it with extra flavor.

You could certainly use a leaner ground beef, but your 5-ingredient White Castle hamburgers won't taste as good as the original. When Cook's Country did a blind taste test of burger meat, the testers described the 80/20 ground chuck as "rich" and "moist." That's important for our copycat White Castle hamburgers, as they don't have any added seasoning. The patties are so small, too, so having enough fat to ensure they won't cook up with a tough texture is critical to pulling off this recipe.

Choosing the right slider bun for 5-ingredient White Castle hamburgers

White Castle's buns have been baked for their restaurants at their Evendale, Ohio, bakery for over 50 years. It's pretty impossible to replicate the exact bun, but you can get pretty close with store-bought options. The ingredients listed on White Castle's frozen sliders are pretty close to several items we found in the bread aisle. We landed on Kroger brand white slider mini buns, but Pepperidge Farm Bakery Classics white slider buns were pretty similar, too.

If you can't find any slider buns, you can either make your own dinner rolls or think outside the box. You're looking for a bun that measures roughly 2-inches around, so King's Hawiian Sweet Bread rolls, Parker House rolls, or any other brand of fresh or frozen dinner rolls should work just fine. You may even be able to cut regular potato rolls in half or quarters to use as slider buns, in a pinch. Just be sure to avoid any tough breads, like baguette or ciabatta, as the texture is too crunchy and chewy to make a good slider bun.

Why use dehydrated onions to make 5-ingredient White Castle hamburgers?

It might seem weird to use dried onions to create 5-ingredient White Castle hamburgers. Why not use fresh onions, like they do at most fast-food restaurants? The short answer is because White Castle uses dehydrated onions, so that's what we used to make our copycat recipe. According to the Whiting-Robertsdale Historical Society, White Castle originally used fresh onions in their famous sliders. In the 1940s, there was an onion shortage, so the company switched to the more readily-available dehydrated version. The swap worked, and the company never went back to the fresh product.

If you prefer to use fresh onions, you absolutely can. Fresh onions have a harsher flavor, so you may want to cook them for longer than the directions below. You'll also want to use at least twice the amount of fresh, finely chopped onions, and you'll still need to add the water to the skillet to ensure there's enough steam to cook the burger patties.

Create the patties for 5-ingredient White Castle hamburgers

Now that we know what to use to create 5-ingredient White Castle hamburgers, it's time to get cooking. Start by measuring out a 10x10 piece of wax paper or parchment paper. It's best to place it on a baking sheet to make it easier to transfer to the freezer later. Then, spread the ground beef onto the paper in a thin, even layer about 1/4-inch thick. Use a butter knife or a pastry cutter to divide the beef into 16 equal portions that measure 2-1/2 inches square.

These sliders will be a little bit bigger than White Castle's, but not by much. According to Cooks Info, one pound of ground beef will make 18 White Castle hamburgers. That means they weigh 25 grams each, or just less than an ounce. Our recipe makes 16 sliders that weigh one ounce each. We originally tried measuring the beef and forming them into square patties, but they were much harder to form into a square shape. They didn't look uniform after cooking, so we prefer the slightly larger, spread-and-cut method.

After you've cut your patties, use your finger or the back of a chopstick to create five holes in each patty. Place the baking sheet in the freezer and let the patties firm up for at least an hour.

Steam the 5-ingredient White Castle hamburgers in the rehydrated onions

Right before you're ready to cook the 5-ingredient White Castle hamburgers, rehydrate the onions by mixing them with the water. Allow the mixture to sit for about five to ten minutes. When the onions are softened, transfer the rehydrated onions and the soaking water water to a skillet or griddle. Bring the mixture to a simmer over medium-high heat before reducing the heat to medium-low. Add the frozen patties and let them steam over the onions for two to three minutes, until the edges start to brown. Feel free to add an extra splash of water if the pan starts to look too dry.

Now, White Castle doesn't flip their burgers. Those five holes we poked into the meat allow the burgers to cook inside and out without the need for flipping, making it faster and more efficient for the fast-food restaurant workers to fulfill orders. Since we're at home, and we're not all trained cooks, we recommend flipping the burger patties. This ensures the meat will be fully cooked on both sides and we won't create the risk of any foodborne illness associated with undercooked meats.

Heat the slider bun to finish these 5-ingredient White Castle hamburgers

After the burger patties are flipped, we're really close to being able to eat these beauties. The only step left is to heat the buns. Some restaurants cook their burger buns directly on the griddle, but White Castle takes advantage of all that steam produced by the onions. Instead of heating the buns separately, they place them on top of the burger patties instead.

Place the slider's bottom bun, cut-side down, on top of each burger patty. Balance the top bun on top of the bottom bun and continue to cook the patties until they're browned through, about two to three minutes. Then, remove the top buns and set them aside while you assemble the burgers. Slide a spatula underneath the patty, grabbing any onions that might be present on the skillet. Flip the burger over so it sits on top of the steamed bottom bun. Top the burger with pickles and add any optional condiments of your choosing, like ketchup, mustard, or mayonnaise. You can also add a half slice of American cheese to each slider to make it a cheeseburger. Add the top bun and serve the 5-ingredient White Castle hamburgers (or cheeseburgers) immediately.

How close did we get to the original White Castle hamburgers?

As far as looks go, we didn't even get close. On our first attempt, the shape of our 5-ingredient White Castle hamburgers was all funky. We tried dividing the beef into 16 one-ounce portions and hand-forming them into 2-1/2-inch squares. They might have tasted like the original, but they didn't look very pretty. In our second go-around, we used the parchment paper and cut method, and the burgers looked a lot more like the original. But, still, they didn't have the precise cut edges you'll find on White Castle's hamburgers.

Appearance aside, this copycat recipe for White Castle hamburgers absolutely worked. They tasted just like the original, with an onion-forward flavor and steamed beef texture. The slider buns we found at the grocery store were spot-on, especially after we steamed them above the burger patties. The burgers tasted great plain, but they were even better with a squirt of ketchup and mustard. All in all, we would absolutely make this recipe again. Delicious, quick, and easy. What more can you ask for?

5-ingredient White Castle hamburgers directions

Prep time: 15 minutes (plus 1 hour freezing time)

Cook time: 6 minutes

Serves: 16 sliders (about four servings)

Ingredients:

  • 1 pound ground beef (preferably 80/20 ground chuck)
  • 1 cup dehydrated or dried onions
  • 1/2 cup water
  • 16 pickles
  • 16 slider buns

Optional ingredients:

  • 8 slices American cheese
  • Condiments, such as ketchup, mustard, or mayonnaise

Directions:

  1. Create a 10x10 piece of wax paper or parchment paper and place it on a baking sheet. Place the ground beef on the paper and spread it until it's a thin, even layer about 1/4-inch thick. Using a butter knife, divide the beef into 16 equal portions to create 2-1/2 inch square patties.
  2. Using your finger or the back of a chopstick, create 5 holes in each patty.
  3. Freeze the patties for an hour.
  4. Rehydrate the onions by mixing them with the water. Allow the mixture to sit for 5 to 10 minutes.
  5. Add the onions and water to a skillet or griddle. Bring the mixture to a simmer over medium-high heat before reducing the heat to medium-low.
  6. Add the frozen patties to the skillet and cook the beef for 2 to 3 minutes, until the edges start to brown. Add additional water if the pan looks too dry.
  7. Flip the hamburger patties and top each one with the slider's bottom bun, cut-side down. Place the top bun cut-side down on top of the bottom bun and continue to cook the patties until they're browned through, an additional 2 to 3 minutes.
  8. Remove the top buns and set aside. Slide a spatula underneath the patty and flip it over onto a plate so it sits on the bottom bun. Top the patty with pickles, a half slice of American cheese (if using), and garnish the burger with the condiments of your choice.
  9. Add the top bun to the burger and serve immediately.