Method: 1. Lightly grease a flat baking sheet. Preheat oven to 190°C/375°F/Gas 5. 2. Put the flour and salt into a bowl, rub in the butter or margarine with tips of fingers. Add sufficient water to mix to a soft dough. Lightly roll in some flour, then cover with cling film and leave in fridge for about 10 minutes. 3. Mix the flour and sugar together in a bowl, add the berries and gently mix until all are coated. 4. Roll crust into a large round and transfer to the prepared tin. Put the blackberry mixture into the centre of the round. Dot with the butter. 5. Bring the excess pastry/crust around the edge onto the berries. Brush with some milk and dust on some sugar. 6. Bake for about 40 minutes until golden brown. 7. Serve hot with whipped cream, ice cream or custard!!