In a food processor, pulse seafood until mixture is well chopped, but not pureed. Transfer to a bowl. Separate dough into individual sections. Flatten each roll. Place 1 tablespoon of the mixture in center of the dough. Gather edges and press to seal. Place buns in a steamer and let cook for 8 to 10 minutes until the dough has puffed up and is cooked through.
To make the dipping sauce, combine the soy sauce and vinegar. Serve with the steamed buns.