In a bowl, combine well the flour, remaining sugar, baking powder, and salt. Blend in the butter until the mixture resembles coarse meal. Add quarter cup boiling water and stir the mixture until it just forms a dough. Bring the blackberry mixture to a boil on top of the stove, stirring. Drop spoonfuls of the dough carefully onto the boiling mixture, and bake the cobbler on a foil lined baking sheet in the middle of a preheated 200ºC oven for 20-25 minutes or until the topping is golden. Serve warm with vanilla ice cream. a 1989 Gourmet Mag. favorite