Spray a 21 cm non-stick bundt pan with oil.
Drain pear slices and reserve juice. Process pears in a food processor or blender to form a smooth puree. Set aside.
Combine reserved pear juice, dates, raisins, currants and sugar in a medium saucepan. Bring to the boil. Gently boil for 5 minutes. Transfer mixture to a large bowl. Stir in bicarb soda. Cool 30 minutes.
Stir in pear puree, eggs and vanilla. Add flour, breadcrumbs and spices. Stir until well combined. Spoon mixture into prepared pan. Smooth over top. Cover cake pan securely with foil.
Bake in a 160 °C oven (fan-forced) for 50 minutes or until a skewer inserted into pudding comes out clean. Stand pudding in pan, covered with foil for 10 minutes, then uncover and turn onto a serving plate.
Meanwhile, to make custard, place custard powder and sugar in a small saucepan. Stir in ¼ cup milk to form a smooth paste. Stir in remaining milk. Cook, stirring constantly over a medium heat until custard boils and thickens.
Dust pudding with icing sugar. Serve sliced with warm custard.