Preparation of Chả Giò fillingsPlace the dried wood ear mushrooms and dried bean vermicelli in separate bowls. Pour enough water over them to fully submerge them. Let them soak for about 15-20 minutes, or until they become soft and pliable. Carefully peel the taro roots using a vegetable peeler or a sharp knife to remove the outer skin. Rinse the peeled taro roots under cold water to remove any residual dirt or starch. Next, use a sharp knife to slice the taro into thin, matchstick-like strands.
Once the bean vermicelli has softened, drain it in a colander to remove excess water. Place the vermicelli on a cutting board and use kitchen scissors or a knife to cut it into shorter strands, about 1 inch in length.
After the wood ear mushrooms have softened, drain them well and gently squeeze out any excess water. Place the mushrooms on a cutting board and use a sharp knife to chop them into finer pieces, aiming for a small, even dice.
In a large mixing bowl, combine the ground pork and crab meat, breaking them up with your hands or a spoon to ensure they are well-mixed. Add the prepared taro strands, chopped wood ear mushrooms, and sliced bean vermicelli to the bowl. If you like, you can also add finely ground shallots for extra flavour. Mix everything together thoroughly until all the ingredients are evenly distributed.
Sprinkle the mixture with salt, pepper, and a small amount of MSG (if using), adjusting the seasoning to taste. Mix everything together until the seasonings are evenly incorporated. The filling should be well-blended, with all the ingredients evenly coated in the seasoning, and ready to be wrapped in the chả giò.
Rolling Chả GiòTake a single sheet of rice paper and briefly dip it into a bowl of warm water, ensuring that it is fully submerged. Let the excess water drip off, and then carefully lay the rice paper flat on a clean surface, such as a cutting board. The rice paper will soften and become more pliable as it sits, making it easier to roll without tearing. Spoon a small portion of the prepared filling, about 2 tablespoons, onto the lower third of the rice paper, near the edge closest to you. Shape the filling into a compact log, leaving some space on either side to fold in the edges. Begin rolling the rice paper away from you, tucking the filling snugly as you go. After making the first roll, fold in the sides of the rice paper over the filling, then continue rolling tightly until you reach the end, creating a neat, sealed roll.
Frying Chả GiòSelect a large, deep frying pan or wok and pour in enough cooking oil to submerge at least half of the spring rolls during frying. Heat the oil over medium-high heat until it reaches the proper frying temperature. Carefully place the prepared spring rolls into the hot oil, making sure not to overcrowd the pan. Depending on the size of your pan, you may need to fry them in batches. Let the spring rolls cook for a few minutes on one side until they start to turn golden brown, then use tongs or a slotted spoon to gently turn them, ensuring that all sides cook evenly. Continue frying until the spring rolls are uniformly golden and crispy.
When the spring rolls are fully cooked, use a slotted spoon or tongs to remove them from the oil and place them on a plate lined with paper towels to drain any excess oil. Allow them to cool slightly, just enough to handle.
Chả Giò is now ready to be served!Serve the golden, crispy spring rolls immediately while they're still hot and crunchy. They are traditionally served with a dipping sauce made from fish sauce, lime juice, sugar, garlic, and chili, which complements the rich flavours of the chả giò perfectly.