Sift flour, baking powder, and salt together. Combine butter and milk, and add to flour mixture, stirring lightly just until all flour is dampened (add a little more milk, if necessary, to form a soft but not runny dough). Drop small amounts from spoon onto simmering stew in deep kettle, resting dumplings on meat or vegetables. Simmer 10 minutes, uncovered. Then cover tightly and cook 10 minutes longer without removing cover. Biscuit mix may be used, adding milk only. It makes richer dough that sometimes falls apart as it cooks.