Shoyu arare (soy sauce caramel rice cracker).
Ume zarame arare (plum and sugar rice cracker).
They are 2 classic flavors for Japanese rice crackers.
You had already seen :
Let’s make 2 new types of Japanese rice crackers. Here is my simplified recipe :
Cut a mochi in cubes.
Everything about mochi (click)
Let dry 2 days.
Toast till golden in the oven toaster.
ザラメ This square candy sugar is called zarame.
For the plum sugar flavor, pass in a mix of pasted umeboshi flesh and sarame sugar, dry in the toaster a few minutes, add more sarame sugar.
For the shoyu, put a block or a tbs of kurozato black sugar in a sauce pan with a little water. When sugar has melted add some soy sauce, simmer till it gets syrupy. Coat the arare.
I have no idea about how long you can keep them. They disappear immediately after the photos are taken.