The Expert-Approved Way To Safely Make An Onion Volcano At Home

When you treat yourself to a night out at hibachi (which is technically, in fact, teppanyaki — something you'll learn if you read this before eating hibachi again), you'll see the chef perform all sorts of showstopping tricks with food. Of all the things you should and shouldn't order at hibachi, a must-try is the famous onion volcano, where domed, stacked slices of onion are set aflame on the grill. 

You may be tempted to try this trick at home, but combining anything with fire comes with safety concerns. For a few pointers, Mashed spoke to chef Steve, owner of Chef Steve Creations, who specializes in mobile hibachi. Chef Steve told Mashed that you can "impress your friends and family while staying safe" if you pay due care and attention when crafting your onion volcano, as this "requires caution to avoid potential hazards."

First and foremost, set up your grill space for safe flambéing. Chef Steves notes it's critical to "ensure that you have nothing flammable near the grill, such as cooking oil" before you even think about setting anything alight. Cooking oil is highly flammable, giving off vapors that can ignite once the oil hits its flashpoint (usually around 600 degrees Fahrenheit). Your oven mitts, towels, and tools such as tongs and spoons should also be kept well away, as even the heat-resistant varieties will catch fire eventually.

To make your onion volcano, follow the technique used by all the best hibachi restaurants in the U.S. Per chef Steve, start by peeling a dome-shaped onion and cut it in half. Then, "separate the rings on one side of the onion and stack them together to form a volcano shape." For the flame, "use a squeeze bottle to pour some oil into the middle of the volcano and add some 80-proof vodka. Ignite the vodka using a lighter, which will create a flame that ignites the fuel." 

In this case, the fuel is the oil. Once the oil burns out, the flame will also go out. But the choice of alcohol is critical: An 80-proof vodka (about 40% alcohol) is important because the higher the alcohol content, the faster it will ignite. Using a much lower proof will result in a very underwhelming display. Alternatively, using a proof that's too high may result in a dangerous eyebrow-eviscerating incident — anything above 120-proof is not recommended.

Even if you've measured everything correctly, you still want to have a safety net if the fire lasts longer than you anticipated. Luckily, chef Steve has advice for this very scenario, too: "If you need to extinguish the flame earlier," he says, "you can slide the onion volcano to a new position on the grill." This will abruptly cut off the flame's access to its fuel, extinguishing it.