However, there's no soy sauce to go with the rice.
I tried searching the market just to check, but it seems like there's nothing similar.
Just like Asura Kingdom, it seems the staple food of Holy Milis Kingdom is bread as well.
Although I've already confirmed that rice exists in this world.
The places where rice is a staple are the Northern and Eastern parts of the Central Continent.
It was written in one of Roxy's letters that rice could be found in Shiron Kingdom as well.
Mixing meat, vegetables, and a variety of fish with rice into something like a paella is the mainstream method supposedly.
However... but...
There's supposedly no poultry industry in that area.
Whether it be because of the climate or they just don't have any chickens, in any case, eggs are almost never found there.