In a large bowl, mix together the mince, the chives along with the salt and pepper. Mix well.
If you are making your own dumpling wrappers, mix the flour with water and knead for 15 minutes or until the dough is nice and soft. Separate the dough into four equal portions. Roll out each of the portions into thin sheets (approx 2mm thick) and use a ring cutter (approximately 7cm in diameter) to cut out circles until all the dough has been used. Skip this step if you are using the pre-made wrappers.
Place about half a tablespoon of filling into the centre of each circle. Fold the circle in half and secure the sides together with a dab of water. Continue this step until the pork mince mixture is all used up. Dust the dumplings with a bit of flour so they don't stick to each other.
Place a frypan on medium-high heat and whilst it heaps up, boil a kettle of water.
Add some oil to the pan, place the dumplings down, they should start sizzling. Let the bottoms colour lightly and then pour boiling water over the dumplings until the water reaches 1/3 up the dumplings.
Cover the pan with a lid and wait for all the water to evaporate. This should take approximately 7 minutes.
Tip the dumplings out upside down on a plate.
For the cucumber salsa, slice wedges of the cucumber by making angular cuts, the wedges do not need to be uniform.
Mix the cucumbers with the rice win, sesame oil, sesame seeds and soy sauce. Combine well and serve with dumplings.