My granny used make these onigiri very often.You can use this pickled plum mixture for all different purposes.
My granny used to make this onigiri for me very often.Just put on rice and eat as it is. Or for pasta and chilled tofu... this plum mixture is quite versatile.My granny used to drink sake with this.
It's very easy! You don't need any tips.
Enjoy Japanese food around the world.