White Castle Sliders: One Man’s Journey for Truth

MYTH BUSTING: There have been a lot of rumors on what exactly a White Castle hamburger is composed of… just go out on the Internet and see for yourself.
Some of the wilder ones are that White Castle hamburgers contain:
• 30% liver… (Yummy)
• 20% beef baby food (I’m not kidding)
• 2 tablespoons of creamy peanut butter per pound of beef
Can you imagine the lawsuits that White Castle would have if they put a nut product in their burgers, and didn’t mention that to anyone? Think of all the people who have allergies to nuts.
For the record, White Castle hamburgers are 100 beef… FULL STOP.
How do I know… Well, because I had one analyzed at a food lab. 100% pure ground beef with a 20% fat content… okay I’m a geek, forgive me.

THEY’RE NOT COOKED… THEY’RE STEAMED: A White Castle hamburger never touches the grill; in essence it rests on a bed of gently cooking onions, and they slowly steam the meat, and the buns.

THE MUSTARD: At the White Castle that I occasioned, they had this wonderful brown mustard. To me, it wasn’t a White Castle hamburger without that mustard. I assumed that all White Castle’s used that mustard; however, they do not. It’s more of a Midwest thing… go figure.
Anyway, for me that “special” mustard was part of the experience. I NEEDED that dang mustard to complete the experience.
You can purchase “White Castle” mustard, but it’s hard to find. I wanted to see if there was a commercial mustard that might do the trick, and 15 bottles of brown mustard later, the winner is: Lowensenf Extra. It’s German brown creamy mustard with just a wonderful hint of vinegar.

SECRET INGREDIENT: If there is a secret ingredient to the White Castle Burger, it’s not peanut butter, baby food (yuk), or liver (double yuk); it’s in the onions. The onions have to be dried, and rehydrated before using.

THE PICKLE: Only one pickle per slider, please. But to cook the pickle or not, that is the question. In the end I cooked the pickle along with the burger. It was a marriage made in heaven.

Movie Trivia: In the movie Harold & Kumar Go to White Castle (yes, they did actually make a movie about White Castle), the actor that played Kumar was a strict vegetarian, so at the end of the movie when they’re scarfing down all those sliders, Kumar’s are veggie burgers… kind of ruins the point of the whole movie.

PREP/PREPARE

Gather your ingredients.

Chef’s Note: In order to get the best visual experience, your patty needs to be the same size as the bun. Mine were 2.5 inches (6.3cm), so I made the raw patties 3 inches (7.5cm), and when they cooked they shrank down to the proper size.

Press the meat out into a square to the dimensions of the four sliders.

Chef's Note: We have enough beef for 4 sliders, so make a square 6x6 inches (12.5cm).

We're adding a bit extra to account for shrinkage during cooking.

Chef’s Note: The beef should be 1/5 inch (.5cm) thick.

Place on a parchment-lined baking sheet, and place in the freezer for 20 minutes.

Remove from freezer, and cut into four equal burgers of 3 inches (7.5cm) each.

Use a soda straw or other small hole punch to create the iconic five holes per burger.

Chef’s Note: Those five holes are not for decoration they are very important to the cooking process. They allow the burger to be cooked without flipping.

Return the burgers to the freezer until completely frozen, about 60 minutes.

Add the onion powder to the hot beef stock and mix to combine.

Rehydrate the onions in the hot beef stock, about 15 minutes.

Chef’s Note: White Castle began using dehydrated onions back during World War II, when most fresh produce was going to the troops. They liked how they worked with the sliders and never stopped using them.

Place a skillet or griddle over medium heat and allow to heat up.

Place an area of onions on the griddle/skillet with a bit of the liquid.

Chef’s Note: the minimum number to cook at a time is 4 sliders.

Place 4 patties on top of the onions, and separate by 1/2 inch (1.2cm).

Place the bottom of the buns, cut side down, on each patty.

Place the top buns across the gaps between the patties.

Allow to steam/cook for 4 to 6 minutes.

Remove the top buns and set aside.

Use a spatula to remove the burgers with the bottom buns, and place on a serving plate.

Add a bit of the mustard, if using, and place the tops on the burgers.

Serve while still warm. Enjoy.

Keep the faith, and keep cooking.