Prepare the mung bean filling, pork, leaves, and rice:
Soak the mung beans for 2 hours. Rinse well and remove any bad beans, then toss with 1 tablespoon salt. Steam the beans until cooked through.
Once the beans are soft, mash them until smooth, then mix with a little ground black pepper (use more or less to taste). Shape the beans into equal-sized balls.

Soak the rice for about 2 hours to soften (no need to soak longer, or the rice will become sour and mushy).
After soaking, rinse the rice several times and remove any bad grains. Toss the rice with 1 tablespoon salt. Let it drain until dry.

Wash the dong leaves thoroughly in water. If not cleaned well, the cake will spoil quickly. Wipe the leaves dry with a clean towel. Cut off the thick veins (but save them to line the pot when boiling the cakes). Be careful not to cut too deep and tear the leaves.

Cut the pork into thick slices, about 3/4 inch (2 cm) thick and 2-2.5 inches (5-6 cm) long. Season with salt and ground black pepper. Now all your ingredients are ready.

Wrapping the cake with a mold:
Arrange the leaves as you would for hand-wrapping. Place the dull sides of two dong leaves overlapping each other, then lay a third leaf, shiny side up, across them. Add another leaf, shiny side up, lengthwise. Stack the leaves, then place the inner mold upside down inside the outer mold.
Next, fit the inner mold into the outer mold, open the leaves, and remove the inner mold. Now you have a neat, square leaf-lined mold. Remove the mold carefully.

Now it's time to add the ingredients. First, pour in one bowl of glutinous rice and spread it evenly in the mold. Add a ball of mung beans and spread it out. Place a piece of seasoned pork in the center, then another ball of mung beans. Finally, add another bowl of glutinous rice on top. Fold the extra leaves neatly and tightly over the cake.

After folding the leaves, press them down with your hand and gently remove the mold. Tie the cake with giang strings—use 2, 3, or 4 strings as you like. The strings should be snug but not too tight, and tie them symmetrically so the cake stays square. Tuck any extra string neatly into the layers.

The cake is now wrapped!

Boiling bánh chưng is the most important step, as it takes a lot of time and effort. When boiling, pack the cakes tightly so they don't break apart as they expand. Add any leftover leaves to the pot for extra flavor and to help retain heat. Traditionally, wood fires give the best flavor and texture, but charcoal stoves also work well.

Before adding the cakes to the pot, line the bottom with giang strings or the thick leaf veins to prevent burning and to keep the boiling water green. Keep the pot at a steady boil and never let it run out of water—keep a bucket of hot water nearby to refill as needed. Never add cold water, as it will cause the cakes to cook unevenly. My family covers the pot with an aluminum basin filled with cold water instead of a lid. As the water heats, we use it to refill the pot, and any leftover is great for washing dishes in winter.

Once the cakes are cooked, remove them from the pot, rinse them clean, and stack them in rows. Use a flat board or tray and a moderate weight to press the cakes and remove excess water. This helps the cakes become firm, flat, and smooth.

The cakes are now pressed and ready!

Enjoy!