Cut the chicken breast into bite-sized pieces.

Boil water in a pot, blanch the okra briefly, drain, and slice into 5mm pieces. Thinly slice the shiso leaf and finely chop the ume plum after removing its seed.

In a bowl, beat the eggs and mix with the remaining egg mixture ingredients to create a smooth egg liquid.

Place the chicken pieces into serving bowls and pour the egg mixture over them.

Place the bowls in a steamer with boiling water, cover, and steam on medium heat for 2 minutes.

Reduce to low heat and steam for another 12–15 minutes with the lid slightly ajar.

Let the steamed chawanmushi cool to room temperature, then refrigerate.