To begin, prepare the batter for the rice noodles. In a large bowl, combine the rice flour, tapioca starch, water, salt, and vegetable oil. Whisk until the mixture is smooth and lump free. Let the batter rest for at least 30 minutes for a smoother texture.

While the batter rests, prepare the filling. Heat 1 tbsp of vegetable oil in a skillet over medium heat. Add the chopped onion and minced garlic, sautéing until fragrant. Add the ground pork and cook until browned, breaking up the meat as it cooks.

Once the pork is cooked, add the chopped wood ear mushrooms, fish sauce, salt, and pepper. Stir well and cook for an additional 3-4 minutes. Set the filling aside to cool slightly while you prepare the rice sheets.

Heat a non-stick pan or a flat-bottomed skillet over medium-low heat. Lightly grease the pan with a thin layer of oil using a brush or paper towel. Stir the batter well before each ladle to ensure even consistency.

Pour a small ladleful of batter into the pan, tilting the pan immediately to create a thin, even layer. Cover the pan and let the rice sheet steam for 1-2 minutes until it becomes translucent and lifts easily from the pan.

Carefully transfer the rice sheet to a clean work surface. Place a spoonful of the pork and mushroom filling along one side of the sheet. Roll the sheet tightly around the filling, creating a soft, translucent roll. Repeat with the remaining batter and filling.

To prepare the dipping sauce (Nuoc Cham), combine fish sauce, warm water, sugar, lime juice, minced garlic, and chili in a small bowl. Stir until the sugar dissolves, adjusting seasoning as needed for a balanced sweet and savoury flavour.

Arrange the Bánh Cuốn rolls on a serving platter. Garnish with fried shallots, fresh herbs, and cucumber slices. Serve alongside the dipping sauce, allowing diners to dip each roll in the sauce to enjoy the full flavour of this classic Vietnamese dish.