Cut off the stems of shiso leaves and slice them thinly.

Heat salad oil in a frying pan over medium heat, add the salmon and cook until browned. Flip, cover with a lid, and steam on low heat for about 3 minutes. Remove skin and bones, then roughly flake the salmon.

In a bowl, mix rice, salmon, shiso, sesame seeds, and salt by cutting through the mixture. Divide into 3 portions, wrap each in plastic wrap, and shape into triangular onigiri.