1.In a small bowl, using an electric mixer, beat butter and sugar together until pale and creamy.
2.Add eggs one at a time, beating well after each addition. Stir in vanilla essence. Lightly fold flour and milk alternately into creamed mixture until combined.
3.Lightly grease a 5-cup pudding basin. Spoon jam into base, then fill with mixture. Cover basin tightly with greased, baking paper, then foil, and secure with kitchen string around the basin’s rim.
4.Place a small trivet in to pressure cooker. Lower pudding onto trivet. Pour in 4 cups boiling water (water should reach no more than halfway up the basin).
5.Close the pressure cooker. Bring up to pressure following the manufactures instructions (until steam escapes at a constant rate and there is a regular hissing sound). Reduce heat. Cook on medium for 40 minutes.
6.Release pressure following instructions. Remove lid and lift pudding from cooker. Set aside 10 minutes. Remove string, foil and paper. Turn onto a plate. Serve hot with cream and custard.
When you tie the baking paper and foil with string, leave a long piece of string to allow for easy removal from the cooker.Note