Chop the crispy plums into small pieces. Mix the plums with the cooked rice in a bowl.

Heat a frying pan over medium heat with salad oil. Crack the eggs into the pan and cook until the edges are golden. Flip and cook until both sides are golden.

Place a sheet of plastic wrap on a flat surface and lay a sheet of roasted nori on top. Add 1/4 of the rice mixture to the center, followed by half the kombu tsukudani, a shiso leaf, a fried egg, and another 1/4 of the rice mixture. Fold the edges of the nori over the filling. Repeat to make two onigirazu.