Simmer the pork fat in water to cover for 15 minutes. Drain, allow to cool, and chop finely.
Cut the salmon into a small dice. Put all the ingredients, except the wonton skins, into a mixing bowl and stir in one direction until mixed.
Spread a wonton skin in front of you. Put 1 teaspoon of the filling in the center of the skin. Dampen the edges of the skin with water and fold in half, pressing the edges to seal. Then, with the folded edge facing you, pull the bottom corners directly down, fold them over one another slightly, and pinch to seal. The resulting dumpling should look like a nurse's cap. Repeat until filling has been used.
Bring a large quantity of water to a boil. When rapidly boiling, add the wontons (not so much that the water will stop boiling, about half), and cook for 3 to 4 minutes or until opaque. Remove, drain, and serve over or with the Coconut Curry Sauce.
Heat a saucepan and add the curry paste. Saute very briefly. Add the coconut milk and chicken stock, and simmer until the sauce reduces by one-third. Set aside.
While boiling the dumplings, reheat the coconut milk mixture; add the fish sauce and lime juice and, when the dumplings are done, drizzle the sauce generously over a serving plate. Sprinkle with the fresh cilantro. Arrange the dumplings over the sauce and serve.
The wontons can be made up to a day ahead and kept refrigerated, lightly covered on a sheet tray. In a pinch they can be frozen and added to the boiling water frozen. (They'll take slightly longer to cook.) You may also stir the cilantro into the sauce and serve it on the side, allowing each diner to help herself.
Recipe courtesy of Big Bowl Noodles and Rice by Bruce Cost with Matt McMillin (HarperCollins, 2000); Photograph by Zeva Oelbaum