Cut 2 nanohana stems for garnish, halve them, and slit the thick parts. Mince the remaining nanohana and ginger.

In a bowl, mix ground pork, minced ginger, and seasonings until sticky. Add minced nanohana and mix well to make the filling.

Place 1/25 of the filling onto each dumpling wrapper. Wet the edges with water and fold to seal, creating pleats. Repeat for all 25 dumplings.

Boil water in a pot and cook 5-6 dumplings at a time until they float. Cook for 1-2 more minutes until the meat is done. Blanch garnish nanohana stems briefly, then cool in water and drain.

Mix soy sauce and mustard paste in a bowl to make the dipping sauce.