In a large bowl combine the flour, baking powder and salt.
In a smaller bowl combine the buttermilk and butter. Add the buttermilk mixture to the flour mixture and stir just until the mix forms a soft dough. Stir in the green onions and thyme.
Drop the dough by the spoonful on to hot simmering stew. Cook, uncovered, for 10 minutes then cover and cook for an extra 10 minutes or until the dumplings are firm but not totally hard.