Add all of the ingredients for the nikuman dough except for the vegetable oil and lukewarm water, and give everything a quick mix.

Whilst mixing the dough with your hand, add the lukewarm water little by little. Next, add the vegetable oil and mix once more.

Tip the dough out of the bowl and knead with your hands. Once smooth, form into a ball, return to the bowl and leave it to prove for 30 minutes whilst covered with a damp cloth.

Finely chop the onion and bamboo shoots into fairly large pieces.

In a separate bowl, add combine all of the nikuman filling ingredients and mix it evenly.

Once the dough has proved, form it into a roughly 40-cm long thin strip and separate into 8 equal pieces.

Roll out each piece of dough into an approximate 10-cm diameter oval shape. Make the center of the dough a bit thicker than the edges to prevent tearing.

Place the filling in the middle of the dough and wrap the dough around whilst creating the nikuman pleats.

Once wrapped, cover the pork buns with a damp cloth and prove for a second time for 15 minutes.

Place the buns in a prepared steamer and steam for 15 minutes to complete.