Put rice in a large bowl, fill with cold water to cover and soak overnight.
Pat pork and add to a bowl with cooking wine and ½ cup of soy sauce. Set aside to marinate.
Boil a large pot of water. Lay out bamboo leaves on a large tray. Once the water starts to boil, remove the water from heat and pour over bamboo leaves. Soak until softened for 15 to 20 minutes. Rinse under cold water, pat dry, trim 1 inch off the end containing the stem.
Drain rice, separate into two bowls and pour half of the remaining soy sauce. Stir to combine.
Place two bamboo leaves on top of each other, with the smaller of the two on top. Create a cone using the trimmed ends. Fill half the cone with rice, add 1 tablespoon of meat, top off the cone with rice. Fold the pointed end of the bamboo leaf over the opening of the cone, leaving a hole of rice visible. Pack rice down tightly, fill the hole with additional rice, repeat 2 to 3 times until full. Slide the third bamboo leaf under the remaining end and fold the existing ends over the third leaf to connect. Fold the third leaf over the side, over the opening, and finish with one more fold around the side. Tie very tightly with two pieces of twine, one horizontally and one vertically.
Fill a pot with dumplings, add enough water to cover, cook on high heat for 6 hours.