Mushroom & Beef & Plenty of Sauce Burger King's Masterpiece Burger 'Winter Special Mushroom Whopper' Tasting Review

Burger King's Mushroom Whopper series is characterized by the juiciness of four kinds of mushrooms and open-fire grilled beef patties. A new ' Winter Special Mushroom Whopper ' using a special sour cream onion sauce was released on Friday, January 9, 2026, so I actually tried it and checked the taste.

'Winter Special Mushroom Whopper' now available! The 'Special Sour Cream Onion Sauce' made with mellow sour cream pairs perfectly with four types of mushrooms.

The 'Winter Special Mushroom Whopper' is advertised on a banner.

I ordered it and brought it home.

I brought home two each of the 'Winter Special Mushroom Whopper,' 'Winter Special Double Mushroom Whopper,' and 'Winter Special Mushroom Whopper Jr.' When ordering multiple burgers at Burger King, it used to be necessary to distinguish between them using handwritten alphabets on the wrappers, but since fall 2025, labels have been attached, making it easier to distinguish between them.

So, I will try the 'Winter Special Mushroom Whopper'.

A single flame-grilled beef patty is piled high with mushrooms, lettuce, onion, and tomato, and is smeared with a generous amount of special sour cream onion sauce and mayonnaise. The four types of mushrooms used are two types of roasted mushrooms, king oyster mushrooms, and bunashimeji mushrooms. The special sour cream onion sauce is made with sour cream, onion paste, oregano, thyme, and celery seed.

The mushrooms are a mix of chewy and crunchy textures, making for a burger that's fun to chew. The special sour cream onion sauce has a slightly tart, refreshing taste that matches the vegetable-packed burger perfectly. The mushrooms and sauce are the main flavors, with the beef patty receding in the background. While all of the Mushroom Whopper series features a fantastic combination of juicy mushrooms with beef and vegetables, the 'Winter Special Mushroom Whopper' is packed with a refreshing sauce, making it even juicier.

I will also try the 'Winter Special Double Mushroom Whopper'.

The burger's composition is almost the same as the 'Winter Special Mushroom Whopper,' with two beef patties added.

The addition of beef patties brings out the flavor of the grilled beef. Previous versions of the Mushroom Whopper series felt like the double patties were too meaty, so the regular patties were a better balance. However, this Mushroom Whopper has a larger amount of sauce, which brings out the flavor of the mushrooms, so the double patties with more meat feel more balanced.

Finally, I eat the 'Winter Special Mushroom Whopper Jr.'

The composition is almost identical to the 'Winter Special Mushroom Whopper.'

The other two types are 'mainly filled with lots of mushrooms and meat, with the bun serving to hold the ingredients in place and make it easier to eat,' but the Jr. has a larger bun volume, making it 'a hamburger with ingredients sandwiched between the bun.' While it has the advantages of being 'small and easy to eat' and 'ingredients don't spill out of the bun, so your fingers don't get dirty,' if you want to enjoy the mushrooms and sauce, we recommend the normal or double size.

The price for the single item is 840 yen including tax for the 'Winter Special Mushroom Whopper', 1190 yen including tax for the 'Winter Special Double Mushroom Whopper', and 540 yen including tax for the 'Winter Special Mushroom Whopper Jr.'