Marinate the pork with 1 tablespoon fish sauce. Soak the wood ear and shiitake mushrooms until soft, then chop them finely. Sauté the shallots until fragrant, add the mushrooms and stir, then add the pork and cook until done. Sprinkle with a little pepper.

Pour warm water into a clean skillet and add 2 tablespoons oil. Dip the rice paper into the skillet, place some of the filling from step 1 onto the rice paper, roll it up, and arrange in a steamer. Steam for 10 minutes, then turn off the heat.

Combine all the dipping sauce ingredients except the garlic and chili in a saucepan. Bring to a boil to dissolve the sugar. Let the mixture cool slightly, then add the minced garlic and chili.