Dumpling: In a small bowl, combine the flour, sugar, baking powder and salt then cut in the cold butter until crumbly. Gradually add milk, tossing with a fork, until dough forms a ball then divide dough in half. Cover and refrigerate for 1 hour or until easy to handle.
On a well floured surface roll each half of dough into a 20cm square. Cut apples in half horizontally then place an apple bottom on each square. Place brown sugar and cinnamon in the core of each then top each with 2 teaspoons butter. Replace apple tops.
Gently bring up corners of pastry to centre then pinch edges to seal. Place in a greased 20cm baking dish. Bake uncovered at 180 degrees C for 15 minutes.
Caramel Sauce: In a small saucepan, combine flour and water until smooth. Add the sugars, butter and salt. Bring to a boil then cook and stir until smooth and blended. Pour over dumplings.
Bake 35-40 minutes longer or until apples are tender and pastry is golden brown.