In a medium-size bowl, add the Stout and corn starch, mixing until the corn starch is blended in. Add the green onions, ginger, garlic, tamari and salt, mixing to combine. Depending on the desired finished texture of the dumpling, one can use a coarser grind of pork to give a more sausage like-bite, or a finer grind to make the filling more like an emulsified hot dog smoothness and have the green onions, garlic and ginger create the pop and texture. Mix in the pork until fully combined.