Home-made onigiri

guys, I got this onigiri recipe from my chef friend and I've been making them a bunch lately — they're perfect for when you have people over. honestly some of my friends straight up don't believe I made them myself and think I just ordered them haha

for rice:
200g sushi rice
240ml water

for marinade:
15g rice vinegar
10g mirin (type of rice wine)
1 tsp sugar
1 tsp salt
1 piece of kombu (5×5cm)

1kg plums
300g shrimps nori

Full recipe here