Mix rice flour and tapioca flour in water until they are completely dissolved. Add salt and oil to the mixture and stir well. Let the batter rest for 20 - 30 minutes.

Chop wood ear mushrooms, carrots, onions, shallots, and scallion finely. Mix them with pork mince and seasoning. Set aside some shallots.

Heat the oil in a skillet over medium heat. Cook some minced garlic and shallots until fragrant, then add the pork mince mixture. Cook the filling over high heat. Constantly stir everything until it is just done. Add some oyster sauce and continue stirring. Remove the cooked filling and let it drain for 10 minutes.

Cook some fried shallots in the skillet. Transfer it to a separate bowl to use as toppings for the finished dish.

If you use a steamer, fill it with water and bring it to a boil. Stretch the steaming cloth over the steamer. Pour a large spoonful or ladleful of rice batter onto the cloth and spread it out thinly and evenly into a round shape. Close the lid and wait for 30 - 40 seconds. Open the lid and check whether the sheet has become semi-translucent. Spread the pork filling on the sheet and roll it up with a bamboo chopstick. If you use a nonstick pan, coat it with a thin layer of oil, then follow the same process as with the steamer.

Make the dipping sauce by mixing Vietnamese fish sauce, sugar, and lemon juice together in warm water. Add minced garlic and red chili. Stir well.

Top the steamed rolled cakes with fried shallots. Serve with Vietnamese cinnamon pork pate, pork sausage, vegetables, and the dipping sauce.