3 cups blueberries, fresh or frozen
¾ cup plain flour
¼ cup milk
1 teaspoon cinnamon
¼ teaspoon vinegar
¼ cup sugar
3 rounded tablespoons red jam
3 tablespoons flour
75g butter, cubed
½ teaspoon baking powder

Put flour, baking powder and butter in to a food processor. Using pulse button, cut butter coarsely, then add mixed milk and vinegar slowly until mixture forms dough. Do not over mix. Cut ball of dough in two. Roll each half thinly, to form a 25cm circle. Line a 20 cm sponge sandwich tin with one circle and cut remaining circle into 10 strips. To prepare filling, heat jam until liquid, then stir in remaining ingredients and pile coated berries in to uncooked crust. Dampen pastry edges with water. Arrange pastry strips in a lattice pattern over filling, cut off pastry 2 cm beyond rim of dish, then turn in edges, enclosing ends of strips. Decorate pastry outer edge, then bake at 210°C, until pastry is golden brown, 25-40 minutes. Serve warm.