Weigh the flours. Soak the mushrooms until soft, then finely chop the mushrooms and onion. Prepare scallion oil with the green onions. Marinate the ground pork with 1 teaspoon seasoning powder, 1 teaspoon sugar, 1 tablespoon fish sauce, black pepper, and minced garlic. Mix well. In a pan, sauté the shallot and garlic until fragrant, then add the pork and stir-fry.

Next, add the mushrooms to the pork. When the pork is cooked through, add the onion and black pepper, stir well, then turn off the heat. Mix all three flours together in a pot with 3 cups water (700 ml), stirring until smooth. Cook over medium heat, stirring constantly to prevent lumps.

As the mixture thickens, lower the heat and keep stirring until the batter turns translucent and is fully cooked. While everything is ready, make a bowl of sweet, spicy, and savory fish sauce.

Spoon the hot bánh đúc into bowls, top with the pork filling, scallion oil, cilantro, and crispy fried shallots. Pour the fish sauce over the rice cake. Bánh đúc is best enjoyed hot.