Preparing foods from other Jewish communities is broadening. It's interesting to sample the foods of other Jewish communities and see what they developed.
A Jewish food is one that is almost sanctified, either by its repeated use or use within the holidays or rituals. So food that may have not been Jewish at one point can become Jewish within the cultural context.
The processing and preparation of food can transform a kosher item into a non-kosher item.
The kosher community tends to follow often several years behind the general societal trends.
There is a biblical injunction to tell your children, but the sages who created the Seder several thousand years ago understood that it had to be more than just speaking: that in order for something to connect so emotionally in human beings, it had to be relived.
Food is sort of like the Jewish sense of humor, a defense mechanism. It is one of the things that helped the Jews survive through 2,000 years of an often very harsh Diaspora.