In a small saucepan, sprinkle the gelatin over the cold bone broth and let it sit for 2 minutes to bloom.
Gently heat the broth over low heat until the gelatin is completely dissolved, then pour it into a shallow container and refrigerate for 2 hours until it sets into a firm jelly.
Once the broth has set, use a knife to finely mince the jelly into very small cubes.
In a medium mixing bowl, combine the ground pork, minced ginger, finely sliced green onions, tamari, sesame oil, sea salt, and black pepper.
Gently fold the minced broth jelly cubes into the pork mixture until evenly distributed.
Place one dumpling wrapper in the palm of your hand and add a tablespoon of the pork filling to the center.
Lightly moisten the edges of the wrapper with water, then pleat the edges upward and pinch the top to seal the dumpling completely.
Line a steamer basket with parchment paper and arrange the dumplings so they are not touching.
Steam over boiling water for 8 to 10 minutes until the pork is cooked through and the broth jelly has melted into a hot soup inside.
Serve the dumplings immediately with a side of rice vinegar for dipping.