(Optional- to sanitize the bamboo leaves, remove them from the soaking liquid and add them to a pot with fresh water. Bring it to a boil and cook the leaves for 5 minutes.) Drain the leaves and wipe them each down on both sides. Cut off an inch from the base and an inch from the tip.
Place the shiitake mushrooms in a medium-sized bowl and add hot water to cover. Soak for 15 to 20 minutes, or until the mushrooms are soft throughout. Drain the mushrooms, squeeze out the excess water, and slice them into quarters.
Drain the rice and transfer it to a big bowl. Add the seasonings to the rice and mix until evenly coated.
Drain the mung beans and transfer them to a medium-sized bowl.
To wrap the zongzi (see the process photos above for the steps)
Take two leaves, making sure they do not have any holes or tears. Use a pair of kitchen scissors to cut off 1” (2.5 cm) from both ends. Face the smooth sides towards yourself (this is the side that will contain the filling), with the wider base sides facing away from each other, then overlap the leaves to make 1 long strip. There should be 3-4” (8-10 cm) of individual leaf sticking out beyond the overlap on each side. A third of the way along the strip, pinch the side opposite from you and fold it into a cone shape, with the leaf sticking out from one end. Hold the cone using one hand and begin to add the filling with your other hand.
Add 2-3 tablespoons of rice to the bottom and press it up against the sides to create a small well. Add a piece of pork (make sure every piece added has a chunk of fat), half a yolk, two quarters a shiitake, and 1 to 2 tablespoons of mung beans. Add 2 to 3 tablespoons of rice over everything. Gently press and smooth as you do. There should be a 1/4” (1/2 cm) lip around the rice.
Take the open side of the zongzi between your thumb and index finger and fold the sides inwards, covering the rice. Fold the long leaves over the open area, tightening between your thumb and index finger to create a pointed triangular shape. Then flip the zongzi over and wrap the leaves around tightly to seal it. Wrap the zongzi in a piece of twine, making sure it is cinching any area where the leaf might come loose, and tie it off. For extra security, you can use another piece of twine to wrap the zongzi again, crosswise.