Steamed Rice Rolls with Char Siu and Nuoc Cham

1 ¼ cup rice flour

¼ cup tapioca starch

3 ½ cup water

1 tsp salt

2 tbsp vegetable oil

1 lb pork shoulder, thinly sliced or cut into 1/2-inch pieces

2 tbsp hoisin sauce

1 ½ tbsp soy sauce, regular or low-sodium

1 tbsp honey

½ tsp Chinese five-spice powder

1 tbsp rice wine or dry sherry

2 clove garlic, minced

1 tsp sesame oil

1 tbsp vegetable oil (for searing)

2 oz shallots (for frying), thinly sliced

¼ cup fish sauce

2 tbsp fresh lime juice, about 1 lime

2 tbsp granulated sugar

2 tbsp water (for nuoc cham)

1 clove garlic (for nuoc cham), minced

1 red chili, thinly sliced (bird's eye or serrano)

¼ cup carrot, finely shredded (optional)

2 tbsp butter or oil (for frying shallots)

½ cup fresh cilantro, leaves only

½ cup thai basil, leaves only

¼ cup mint, leaves only

8 butter lettuce or lettuce leaves, small leaves for serving

1 cup bean sprouts, rinsed