They're calling it "Okonomiyaki Crispy Chicken" as it draws its inspiration from okonomiyaki--a Japanese savory pancake.
The mayo, bonito flakes, and sauce are regular toppings for okonomiyaki. The fried chicken itself appears to be the brand's regular fried bone-in chicken rather than any special breading or a boneless filet. While they're called flakes, bonito flakes are more like paper-thin shavings. Okonomiyaki sauce is similar to a thickened sweet and tangy soy sauce.
Image via KFC Hong Kong.
