How do I unlock Gunkan-Maki with two toppings?
I have unlocked both the two ingredients/two toppings Nigiri and the three ingredients Makizushi in the game, but I never found out how to get an additional topping for the Gunkan-Maki. Is it available in the game, and how can you unlock it?
There is no 2nd topping for the Gunkan-Maki.
If you take a look at all the contest rewards You'll see that there are only rewards for unlocking additional ingredients to the maki and nigiri.