Soften the yeast in the water. Add the flour, salt, sugar and butter. Mix, adding more water if needed to make a moderately stiff dough. Knead on a lightly floured surface for ten to fifteen minutes, or until very smooth and elastic.
Place in a lightly greased bowl, turn over to grease the top, cover, and let the dough rise in a warm place for about one hour, until doubled in bulk. While the dough is rising, prepare the meat mixture.
Preheat oven to hot (450°F.).
Divide the raised dough into twelve portions. Shape it into balls and let stand for ten minutes.
Roll or press each ball into a six-inch round. Place the rounds on a greased baking sheet. Spread each round to the edge with some of the prepared filling.
Bake the pastries for about fifteen minutes, until crust is golden. Serve immediately, or cool on a rack and reheat before serving.