Jam Pudding

Name: Jam Pudding
Yield: Serves 6
Ingredients: 170 g (6 oz/¾ cup) caster (superfine) sugar; 60 g (2¼ oz/½ cup) plain (all-purpose) flour; 3 eggs; 125 g (4½ oz/1 cup) self-raising flour; 1 teaspoon vanilla extract; 185 g (6½ oz) unsalted butter, softened; 160 g (5½ oz/½ cup) berry jam