I tried Burger King's 'Big Mouth Inferno Burger' with spicy smoked garlic flakes

Burger King's 'Big Mouth' series has introduced two new 'Inferno' varieties, which feature flame-grilled beef patties and 'smoked spicy garlic flakes,' so I went to Burger King to try them.

Burger King's popular 'Big Mouth' series introduces the new, deliciously spicy 'Inferno'! The addictive flavor of flame-grilled beef and 'smoked spicy garlic flakes' is sure to be a hit! Two new flavors are now available: 'Double Beef' and 'Chicken & Beef.'
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'Big Mouth Inferno Burger' released today!

This large burger is made with flame-grilled beef topped with 'smoked spicy garlic flakes,' allowing you to enjoy the savory, smoky flavor and addictive spiciness!

Choose from two options: 'Double Beef' or 'Chicken & Beef'! #BurgerKingpic.twitter.com /PpoXxo0Xgc

— Burger King Japan (@BURGERKINGJAPAN) August 21, 2025

Arrived at Burger King.

Two varieties of 'Big Mouth Inferno' were placed at the top of the limited-time menu.

It was a busy lunchtime, but I was able to receive my order in less than 10 minutes. The one on the left, labeled 'DB,' is the 'Double Beef Big Mouth Inferno Burger,' and the one on the right, labeled 'CB,' is the 'Chicken & Beef Big Mouth Inferno Burger.'

When I opened the 'Double Beef' package, I found a hamburger of a fairly standard size for Burger King.

As the name 'Double Beef' suggests, there are two patties and plenty of cheese on top.

When I lifted the top bun, I found bacon with ketchup inside.

You wouldn't know it from the outside, but there are actually 'smoked spicy garlic flakes' sandwiched between the patties, and a special spicy sauce is also used.

The first bite is a massive patty, and it's 'meat, meat, and more meat,' but a tingling spiciness hits immediately after. While the press release describes the spiciness as 'delicious and spicy' and 'addictively spicy,' without any mention of the intensity of the spiciness, even our editors, who are fairly comfortable with spicy food, were surprised by the spiciness. The spiciness blends with the generous amount of beef in the mouth, stimulating the appetite. The garlic flakes are slightly soft and supple, rather than crunchy like 'edible chili oil,' and the bacon is barely noticeable, so the sensation of eating it is like stepping on soft snow, draining the moisture from your mouth. In addition to the spiciness, the saltiness is also quite strong, so I recommend ordering a medium or larger drink instead of a small one.

On the other hand, 'Chicken & Beef' has a chicken patty hiding the beef patty.

The generous amount of cheese sauce stuck the top bun to the chicken patty, making it difficult to separate.

This one also has plenty of garlic flakes between the patties.

The patties have changed from two beef patties to one chicken and one beef, and the sauce has also changed from the special spicy sauce to Bullseye BBQ sauce, making it look and feel completely different. The Bullseye BBQ Burger isn't supposed to be spicy, but the light flavor of the chicken patty enhances the spiciness of the garlic flakes, making this burger feel a little spicier. This one, too, makes you want a larger drink. The thickness and crunchy texture of the chicken patty allowed me to fully enjoy the Big Mouth series' 'open your mouth wide and bite into it' experience.

Although the 'Big Mouth' burger sounds like it would be high in calories, the 'Double Beef' burger is 909 kcal, and the 'Chicken & Beef' burger is 776 kcal, which is light for this type of burger.

The 'Double Beef Big Mouth Inferno Burger' is priced at 1,490 yen (tax included) and the 'Chicken & Beef Big Mouth Inferno Burger' is priced at 1,290 yen (tax included) and will be available for a limited time from Friday, August 22, 2025. Please note that this item is not available at the Tokyo Racecourse store, Tsugaike Snow Square store, or Kyoto Racecourse store.